A century of science in America

by Unknown

“PLAN OF THE WORK.

This Journal is intended to embrace the circle of The Physical Sciences, with their application to The Arts, and to every useful purpose.

It is designed as a deposit for original American communications; but will contain also occasional selections from Foreign Journals, and notices of the progress of science in other countries. Within its plan are embraced

Natural History, in its three great departments of Mineralogy, Botany, and Zoology;

Chemistry and Natural Philosophy, in their various branches: and Mathematics, pure and mixed.

It will be a leading object to illustrate American Natural History, and especially our Mineralogy and Geology.

The Applications of these sciences are obviously as numerous as physical arts, and physical wants; for no one of these arts or wants can be named which is not connected with them.

While Science will be cherished for its own sake, and with a due respect for its own inherent dignity; it will also be employed as the handmaid to the Arts. Its numerous applications to Agriculture, the earliest and most important of them; to our Manufactures, both mechanical and chemical; and to our Domestic Economy, will be carefully sought out, and faithfully made.

It is also within the design of this Journal to receive communications on Music, Sculpture, Engraving, Painting, and generally on the fine and liberal, as well as useful arts;

On Military and Civil Engineering, and the art of Navigation.

Notices, Reviews, and Analyses of new scientific works, and of new Inventions, and Specifications of Patents;

Biographical and Obituary Notices of scientific men; essays on Comparative Anatomy and Physiology, and generally on such other branches of medicine as depend on scientific principles;

Meteorological Registers, and Reports of Agricultural Experiments: and we would leave room also for interesting miscellaneous things, not perhaps exactly included under either of the above heads.

Communications are respectfully solicited from men of science, and from men versed in the practical arts.

Learned Societies are invited to make this Journal, occasionally, the vehicle of their communications to the Public.

The editor will not hold himself responsible for the sentiments and opinions advanced by his correspondents; but he will consider it as an allowed liberty to make slight verbal alterations, where errors may be presumed to have arisen from inadvertency.”

In the “Advertisement” which precedes the above statement in the first number, the editor remarks somewhat naïvely that he “does not pledge himself that all the subjects shall be touched upon in every number. This is plainly impossible unless every article should be very short and imperfect....”

The whole subject is discussed in all its relations in the “Introductory Remarks” which open the first volume. No apology is needed for quoting at considerable length, for only in this way can the situation be made clear, as seen by the editor in 1818. Further we gain here a picture of the intellectual life of the times and, not less interesting, of the mind and personality of the writer. With a frank kindliness, eminently characteristic of the man, as will be seen, he takes the public fully into his confidence. In the remarks made in subsequent volumes,—also extensively quoted—the vicissitudes in the conduct of the enterprise are brought out and when success was no longer doubtful, there is a tone of quiet satisfaction which was also characteristic and which the circumstances fully justified.

The Introductory Remarks begin as follows:

The age in which we live is not less distinguished by a vigorous and successful cultivation of physical science, than by its numerous and important applications to the practical arts, and to the common purposes of life.

In every enlightened country, men illustrious for talent, worth and knowledge, are ardently engaged in enlarging the boundaries of natural science; and the history of their labors and discoveries is communicated to the world chiefly through the medium of scientific journals. The utility of such journals has thus become generally evident; they are the heralds of science; they proclaim its toils and its achievements; they demonstrate its intimate connection as well with the comfort, as with the intellectual and moral improvement of our species; and they often procure for it enviable honors and substantial rewards.

Mention is then made of the journals existing in England and France in 1818 “which have long enjoyed a high and deserved reputation.” He then continues:

From these sources our country reaps and will long continue to reap, an abundant harvest of information: and if the light of science, as well as of day, springs from the East, we will welcome the rays of both; nor should national pride induce us to reject so rich an offering.

But can we do nothing in return?

In a general diffusion of useful information through the various classes of society, in activity of intellect and fertility of resource and invention, producing a highly intelligent population, we have no reason to shrink from a comparison with any country. But the devoted cultivators of science in the United States are comparatively few: they are, however, rapidly increasing in number. Among them are persons distinguished for their capacity and attainments, and, notwithstanding the local feelings nourished by our state sovereignties, and the rival claims of several of our larger cities, there is evidently a predisposition towards a concentration of effort, from which we may hope for the happiest results, with regard to the advancement of both the science and reputation of our country.

Is it not, therefore, desirable to furnish some rallying point, some object sufficiently interesting to be nurtured by common efforts, and thus to become the basis of an enduring, common interest? To produce these efforts, and to excite this interest, nothing, perhaps, bids fairer than a Scientific Journal.

The valuable work already accomplished by various medical journals is then spoken of and particularly that of the first scientific periodical in the United States, Bruce’s Mineralogical Journal. This, as Silliman says (1, p. 3, 1818), although “both in this country and in Europe received in a very flattering manner,” did not survive the death of its founder, and only a single volume of 270 pages appeared (1810–1813).

Silliman continues:

No one, it is presumed, will doubt that a journal devoted to science, and embracing a sphere sufficiently extensive to allure to its support the principal scientific men of our country, is greatly needed; if cordially supported, it will be successful, and if successful, it will be a great public benefit.

Even a failure, in so good a cause, (unless it should arise from incapacity or unfaithfulness,) cannot be regarded as dishonourable. It may prove only that the attempt was premature, and that our country is not yet ripe for such an undertaking; for without the efficient support of talent, knowledge, and money, it cannot long proceed. No editor can hope to carry forward such a work without the active aid of scientific and practical men; but, at the same time, the public have a right to expect that he will not be sparing of his own labour, and that his work shall be generally marked by the impress of his own hand. To this extent the editor cheerfully acknowledges his obligations to the public; and it will be his endeavour faithfully to redeem his pledge.

Most of the periodical works of our country have been short-lived. This, also, may perish in its infancy; and if any degree of confidence is cherished that it will attain a maturer age, it is derived from the obvious and intrinsic importance of the undertaking; from its being built upon permanent and momentous national interests; from the evidence of a decided approbation of the design, on the part of gentlemen of the first eminence, obtained in the progress of an extensive correspondence; from assurance of support, in the way of contributions, from men of ability in many sections of the union; and from the existence of such a crisis in the affairs of this country and of the world, as appears peculiarly auspicious to the success of every wise and good undertaking.

An interesting discussion follows (pp. 5–8) as to the claims of the different branches of science, and the extent to which they and their applications had been already developed, also the spheres still open to discovery.

The Introductory Remarks close, as follows:

In a word, the whole circle of physical science is directly applicable to human wants and constantly holds out a light to the practical arts; it thus polishes and benefits society and everywhere demonstrates both supreme intelligence and harmony and beneficence of design in the Creator.

The science of mathematics, both pure and mixed, can never cease to be interesting and important to man, as long as the relations of quantity shall exist, as long as ships shall traverse the ocean, as long as man shall measure the surface or heights of the earth on which he lives, or calculate the distances and examine the relations of the planets and stars; and as long as the iron reign of war shall demand the discharge of projectiles, or the construction of complicated defences.

The closing part of the paragraph shows the influence exerted upon the mind of the editor by the serious wars of the years preceding 1818, a subject alluded to again at the close of this chapter.

In February, 1822, with the completion of the fourth volume, the editor reviews the situation which, though encouraging is by no means fully assuring. He says (preface to vol. 4, dated Feb. 15, 1822):

Two years and a half have elapsed, since the publication of the first volume of this Journal, and one year and ten months since the Editor assumed the pecuniary responsibility....

The work has not, even yet, reimbursed its expenses, (we speak not of editorial or of business compensation,) we intend, that it has not paid for the paper, printing and engraving; the proprietors of the first volume being in advance, on those accounts, and the Editor on the same score, with respect to the aggregate expense of the three last volumes. This deficit is, however, no longer increasing, as the receipts, at present, just about cover the expense of the physical materials, and of the manual labour. A reiterated disclosure of this kind is not grateful, and would scarcely be manly, were it not that the public, who alone have the power to remove the difficulty, have a right to a frank exposition of the state of the case. As the patronage is, however, growing gradually more extensive, it is believed that the work will be eventually sustained, although it may be long before it will command any thing but gratuitous intellectual labour....

These facts, with the obvious one,—that its pages are supplied with contributions from all parts of the Union, and occasionally from Europe, evince that the work is received as a national and not as a local undertaking, and that the community consider it as having no sectional character. Encouraged by this view of the subject, and by the favour of many distinguished men, both at home and abroad, and supported by able contributors, to whom the Editor again tenders his grateful acknowledgments, he will still persevere, in the hope of contributing something to the advancement of our science and arts, and towards the elevation of our national character.

In the autumn of the same year, the editor closes the fifth volume with a more confident tone (Sept. 25, 1822):

A trial of four years has decided the point, that the American Public will support this Journal. Its pecuniary patronage is now such, that although not a lucrative, it is no longer a hazardous enterprise. It is now also decided, that the intellectual resources of the country are sufficient to afford an unfailing supply of valuable original communications and that nothing but perseverance and effort are necessary to give perpetuity to the undertaking.

The decided and uniform expression of public favour which the Journal has received both at home and abroad, affords the Editor such encouragement, that he cannot hesitate to persevere—and he now renews the expression of his thanks to the friends and correspondents of the work, both in Europe and the United States, requesting at the same time a continuance of their friendly influence and efforts.

Still again in the preface to the sixth volume (1823) he takes the reader more fully into his confidence and shows that he regards the enterprise as no longer of doubtful success. He says:

The conclusion of a new volume of a work, involving so much care, labour and responsibility, as are necessarily attached, at the present day, to a Journal of Science and the Arts, naturally produces in the mind, a state of not ungrateful calmness, and a disposition, partaking of social feeling, to say something to those who honour such a production, by giving to it a small share of their money, and of their time. The Editor’s first impression was, that the sixth volume should be sent into the world without an introductory note, but he yields to the impulse already expressed, and to the established usages of respectful courtesy to the public, which a short preface seems to imply. He has now persevered almost five years, in an undertaking, regarded by many of the friends whom he originally consulted, as hazardous, and to which not a few of them prophetically alloted only an ephemeral existence. It has been his fortune to prosecute this work without, (till a very recent period,) returns, adequate to its indispensable responsibilities;—under a heavy pressure of professional and private duty; with trying fluctuations of health, and amidst severe and reiterated domestic afflictions. The world are usually indulgent to allusions of this nature, when they have any relation to the discharge of public duty; and in this view, it is with satisfaction, that the Editor adds, that he has now to look on formidable difficulties, only in retrospect, and with something of the feeling of him, who sees a powerful and vanquished foe, slowly retiring, and leaving a field no longer contested.

This Journal which, from the first, was fully supplied with original communications, is now sustained by actual payment, to such an extent, that it may fairly be considered as an established work; its patronage is regularly increasing, and we trust it will no longer justify such remarks as some of the following, from the pen of one of the most eminent scientific men in Europe. “Nothing surprises me more, than the little encouragement which your Journal,” (“which I always read with very great interest, and of which I make great use,”) “experiences in America—this must surely arise from the present depressed condition of trade, and cannot long continue.”

Six years more of uninterrupted editorial work passed by, the sixteenth volume was completed, and the editor was now in a position to review the whole situation up to 1829. This preface (dated July 1, 1829), which is quoted nearly in full, cannot fail to be found particularly interesting and from several standpoints, not the least for the insight it gives into the writer’s mind. It is also noteworthy that at this early date it was found possible to pay for original contributions, a privilege far beyond the means of the editor of to-day.

When this Journal was first projected, very few believed that it would succeed.

Among others, Dr. Dorsey wrote to the editor; “I predict a short life for you, although I wish, as the Spaniards say, that you may live a thousand years.” The work has not lived a thousand years, but as it has survived more than the hundredth part of that period, no reason is apparent why it may not continue to exist. To the contributors, disinterested and arduous as have been their exertions, the editor’s warmest thanks are due; and they are equally rendered to numerous personal friends for their unwavering support: nor ought those subscribers to be forgotten who, occupied in the common pursuits of life, have aided, by their money, in sustaining the hazardous novelty of an American Journal of Science. A general approbation, sufficiently decided to encourage effort, where there was no other reward, has supported the editor; but he has not been inattentive to the voice of criticism, whether it has reached him in the tones of candor and kindness, or in those of severity. We must not look to our friends for the full picture of our faults. He is unwise who neglects the maxim—

—fas est ab hoste doceri,

and we may be sure, that those are quite in earnest, whose pleasure it is, to place faults in a strong light and bold relief; and to throw excellencies into the shadow of total eclipse. Minds at once enlightened and amiable, viewing both in their proper proportions, will however render the equitable verdict;

Non ego paucis offendar maculis,—

It is not pretended that this Journal has been faultless; there may be communications in it which had been better omitted, and it is not doubted that the power to command intellectual effort, by suitable pecuniary reward, would add to its purity, as a record of science, and to its richness, as a repository of discoveries in the arts.

But the editor, even now, offers payment, at the rate adopted by the literary Journals, for able original communications, containing especially important facts, investigations and discoveries in science, and practical inventions in the useful and ornamental Arts.

As however his means are insufficient to pay for all the copy, it is earnestly requested, that those gentlemen, who, from other motives, are still willing to write for this Journal, should continue to favor it with their communications. That the period when satisfactory compensation can be made to all writers whose pieces are inserted, and to whom payment will be acceptable, is not distant, may perhaps be hoped, from the spontaneous expression of the following opinion, by the distinguished editor of one of our principal literary journals, whose letter is now before me. “The character of the American Journal is strictly national, and it is the only vehicle of communication in which an inquirer may be sure to find what is most interesting in the wide range of topics, which its design embraces. It has become in short, not more identified with the science than the literature of the country.” It is believed that a strict examination of its contents will prove that its character has been decidedly scientific; and the opinion is often expressed to the editor, that in common with the journals of our Academies, it is a work of reference, indispensable to him who would examine the progress of American science during the period which it covers. That it might not be too repulsive to the general reader, some miscellaneous pieces have occasionally occupied its pages; but in smaller proportion, than is common with several of the most distinguished British Journals of Science.

Still, the editor has been frequently solicited, both in public and private, to make it more miscellaneous, that it might be more acceptable to the intelligent and well educated man, who does not cultivate science; but he has never lost sight of his great object, which was to produce and concentrate original American effort in science, and thus he has foregone pecuniary returns, which by pursuing the other course, might have been rendered important. Others would not have him admit any thing that is not strictly and technically scientific; and would make this journal for mere professors and amateurs; especially in regard to those numerous details in natural history, which although important to be registered, (and which, when presented, have always been recorded in the American Journal,) can never exclusively occupy the pages of any such work without repelling the majority of readers.

If this is true even in Great Britain it is still more so in this country; and our savants, unless they would be, not only the exclusive admirers, but the sole purchasers of their own works, must permit a little of the graceful drapery of general literature to flow around the cold statues of science. The editor of this Journal, strongly inclined, both from opinion and habit, to gratify the cultivators of science, will still do everything in his power to promote its high interests, and as he hopes in a better manner than heretofore; but these respectable gentlemen will have the courtesy, to yield something to the reading literary, as well as scientific public, and will not, we trust, be disgusted, if now and then an Oasis relieves the eye, and a living stream refreshes the traveller. Not being inclined to renew the abortive experiment, to please every body, which has been so long renowned in fable; the editor will endeavor to pursue, the even tenor of his way; altogther inclined to be courteous and useful to his fellow travellers, and hoping for their kindness and services in return.

The Close of the First Series.

The “First Series,” as it was henceforth to be known, closed with the fiftieth volume (1847, pp. xx + 347). This final volume is devoted to an exhaustive index to the forty-nine volumes preceding. In the preface (dated April 19, 1847) the elder Silliman, now the senior editor, reviews the work that had been accomplished with a frank expression of his feeling of satisfaction in the victory won against great obstacles; with this every reader must sympathize. He quotes here at length (but in slightly altered form) the matter from the first volume (1818), which has been already reproduced almost entire, and then goes on as follows (pp. xi et seq.):

Such was the pledge which, on entering upon our editorial labors in 1818, we gave to the public, and such were the views which we then entertained, regarding science and the arts as connected with the interests and honor of our country and of mankind. In the retrospect, we realize a sober but grateful feeling of satisfaction, in having, to the extent of our power, discharged these self-imposed obligations; this feeling is chastened also by a deep sense of gratitude, first to God for life and power continued for so high a purpose; and next, to our noble band of contributors, whose labors are recorded in half a century of volumes, and in more than a quarter of a century of years. We need not conceal our conviction, that the views expressed in these “Introductory Remarks,” have been fully sustained by our fellow laborers.

Should we appear to take higher ground than becomes us, we find our vindication in the fact, that we have heralded chiefly the doings and the fame of others. The work has indeed borne throughout “the impress” of editorial unity of design, and much that has flowed from one pen, and not a little from the pens of others, has been without a name. The materials for the pile, have however been selected and brought in, chiefly by other hands, and if the monument which has been reared should prove to be “aere perennius,” the honor is not the sole property of the architect; those who have quarried, hewn and polished the granite and the marble, are fully entitled to the enduring record of their names already deeply cut into the massy blocks, which themselves have furnished.

If a retrospective survey of the labors of thirty years on this occasion has rekindled a degree of enthusiasm, it is a natural result of an examination of all our volumes from the contents of which we have endeavored to make out a summary both of the laborers and their works....

The series of volumes must ever form a work of permanent interest on account of its exhibiting the progress of American science during the long period which it covers. Comparing 1817 with 1847, we mark on this subject a very gratifying change. The cultivators of science in the United States were then few—now they are numerous. Societies and associations of various names, for the cultivation of natural history, have been instituted in very many of our cities and towns, and several of them have been active and efficient in making original observations and forming collections.

A summary follows presenting some facts as to the growth of scientific societies and scientific collections in this country during the period involved: Then the striking contrast between 1818 and 1847 in the matter of organized effort toward scientific exploration is discussed, as follows (pp. xvi et seq.):

When we began our Journal, not one of the States had been surveyed in relation to its geology and natural history; now those that have not been explored are few in number. State collections and a United States Museum hold forth many allurements to the young naturalist, as well as to the archaeologist and the student of his own race. The late Exploring Expedition [Wilkes] with the National Institute, has enriched the capital with treasures rarely equalled in any country, and the Smithsonian Institution recently organized at Washington, is about to begin its labors for the increase and diffusion of knowledge among men.

It must not be forgotten that the American Association of Geologists and Naturalists—composed of individuals assembled from widely separate portions of the Union—by the seven sessions which it has held, and by its rich volume of reports, has produced a concentration and harmony of effort which promise happy results, especially as, like the British Association, it visits different towns and cities in its annual progress.

Astronomy now lifts its exploring tubes from the observatories of many of our institutions. Even the Ohio, which within the memory of the oldest living men, rolled along its dark waters through interminable forests, or received the stains of blood from deadly Indian warfare, now beholds on one of its most beautiful hills, and near its splendid city, a permanent observatory with a noble telescope sweeping the heavens, by the hand of a zealous and gifted observer. At Washington also, under the powerful patronage of the general government, an excellent observatory has been established, and is furnished with superior instruments, under the direction of a vigilant and well instructed astronomer—seconded by able and zealous assistants.

Here also (in Yale College) successful observations have been made with good instruments, although no permanent building has been erected for an Observatory.

We only give single examples by way of illustration, for the history of the progress of science in the United States, and of institutions for its promotion, during the present generation, would demand a volume. It is enough for our purpose that science is understood and valued, and the right methods of prosecuting it are known, and the time is at hand when its moral and intellectual use will be as obvious as its physical applications. Nor is it to be forgotten that we have awakened an European interest in our researches: general science has been illustrated by treasures of facts drawn from this country, and our discoveries are eagerly sought for and published abroad.

While with our co-workers in many parts of our broad land, we rejoice in this auspicious change, we are far from arrogating it to ourselves. Multiplied labors of many hands have produced the great results. In the place which we have occupied, we have persevered despite of all discouragements, and may, with our numerous coadjutors, claim some share in the honors of the day. We do not say that our work might not have been better done—but we may declare with truth that we have done all in our power, and it is something to have excited many others to effort and to have chronicled their deeds in our annals. Let those that follow us labor with like zeal and perseverance, and the good cause will continue to advance and prosper. It is the cause of truth—science is only embodied and sympathized truth and in the beautiful conception of our noble Agassiz—“it tells the thought of God.”

The preface closes with some personal remarks:

In tracing back the associations of many gone-by years, a host of thoughts rush in, and pensive remembrance of the dead who have labored with us casts deep shadows into the vista through which we view the past.

Anticipation of the hour of discharge, when our summons shall arrive, gives sobriety to thought and checks the confidence which health and continued power to act might naturally inspire, were we not reproved, almost every day, by the death of some co-eval, co-worker, companion, friend or patron. This very hour is saddened by such an event,—but we will continue to labor on, and strive to be found at our post of duty, until there is nothing more for us to do; trusting our hopes for a future life in the hands of Him who placed us in the midst of the splendid garniture of this lower world, and who has made not less ample provision for another and a better.

Editorial and financial.—The editorial labors on the Journal were carried by the elder Silliman alone for twenty years from 1818 to 1838. As has been clearly shown in his statements, already quoted, he was, after the first beginning, personally responsible also for the financial side of the enterprise. With volume 34 (1838) the name of Benjamin Silliman, Jr., is added as co-editor on the title page. He was graduated from Yale College the year preceding and at this date was only twenty-one years old. His aid was unquestionably of much service from the beginning and increased rapidly with years and experience. The elder Silliman introduces him in the preface to vol. 34 (1838) and comes back to the subject again in the preface to vol. 50 (1847). The whole editorial situation is here presented as follows:

“During twenty years from the inception of this Journal, the editor labored alone, although overtures for editorial cooperation had been made to him by gentlemen commanding his confidence and esteem, and who would personally have been very acceptable. It was, however, his opinion that the unity of purpose and action so essential to the success of such a work were best secured by individuality; but he made every effort, and not without success, to conciliate the good will and to secure the assistance of gentlemen eminent in particular departments of knowledge. On the title page of No. 1, vol. 34, published in July, 1838, a new name is introduced: the individual to whom it belongs having been for several years more or less concerned in the management of the Journal, and from his education, position, pursuits and taste, as well as from affinity, being almost identified with the editor, he seemed to be quite a natural ally, and his adoption into the editorship was scarcely a violation of individual unity. His assistance has proved to be very important:—his near relation to the senior editor prevents him from saying more, while justice does not permit him to say less.”

As is distinctly intimated in the preceding paragraph the elder Silliman was fortunate in obtaining the assistance in his editorial labors of numerous gentlemen interested in the enterprise. Their cooperation provided many of the scientific notices, book reviews and the like contained in the Miscellany with which each number closed. It is impossible, at this date, to render the credit due to Silliman’s helpers or even to mention them by name. Very early Asa Gray was one of these as occasional notes are signed by his initials. Dr. Levi Ives of New Haven was another. Prof. J. Griscom of Paris also sent numerous contributions even as early as 1825 (see 9, 154, 1825; 22, 192, 1832; 24, 342, 1833, and others).

Some statements have already been quoted from the early volumes as to the business part of Silliman’s enterprise. The subject is taken up more fully in the preface to volume 50 (1847). No one can fail to marvel at the energy and optimism required to push the Journal forward when conditions must have been so difficult and encouragement so scanty. He says (pp. iii, iv):

This Journal first appeared in July, 1818, and in June, 1819, the first volume of four numbers and 448 pages was completed. This scale of publication, originally deemed sufficient, was found inadequate to receive all the communications, and as the receipts proved insufficient to sustain the expenses, the work, having but three hundred and fifty subscribers, was, at the end of the year, abandoned by the publishers.

An unprofitable enterprise not being attractive to the trade, ten months elapsed before another arrangement could be carried into effect, and, therefore, No. 1 of vol. 2 was not published until April, 1820. The new arrangement was one of mutual responsibility for the expenses, but the Editor was constrained nevertheless to pledge his own personal credit to obtain from a bank the funds necessary to begin again, and from this responsibility he was, for a series of years, seldom released. The single volume per annum being found insufficient for the communications, two volumes a year were afterward published, commencing with the second volume.

The publishers whose names appear on the title page of the four numbers of the first volume are “J. Eastburn & Co., Literary Rooms, Broadway, New York” and “Howe & Spalding, New Haven.” For the second volume and those immediately following the corresponding statement “printed and published by S. Converse [New Haven] for the Editor.”

Silliman adds (p. iv):

At the conclusion of vol. 10, in February, 1826, the work was again left upon the hands of its Editor; all its receipts had been absorbed by the expenses, and it became necessary now to pay a heavy sum to the retiring publisher, as an equivalent for his copies of previous volumes, as it was deemed necessary either to control the work entirely or to abandon it. The Editor was not willing to think of the latter, especially as he was encouraged by public approbation, and was cheered onward in his labors by eminent men both at home and abroad, and he saw distinctly that the Journal was rendering service not only to science and the arts, but to the reputation of his country. He reflected, moreover, that in almost every valuable enterprise perseverance in effort is necessary to success. He being now sole proprietor, a new arrangement was made for a single year, the publishers being at liberty, at the end of that time, to retire, and the Editor to resume the Journal should he prefer that course.

The latter alternative he adopted, taking upon himself the entire concern, including both the business and the editorial duties, and of course, all the correspondence and accounts. From that time the work has proceeded without interruption, two volumes per annum having been published for the last twenty years; and its pecuniary claims ceased to be onerous, although its means have never been large....

Later in the same preface he adds (p. xiv):

It may be interesting to our readers to know something of the patronage of the Journal. It has never reached one thousand paying subscribers, and has rarely exceeded seven or eight hundred—for many years it fluctuated between six and seven hundred.

It has been far from paying a reasonable editorial compensation; often it has paid nothing, and at present it does little more than pay its bills. The number of engravings and the extra labor in printer’s composition, cause it to be an expensive work, while its patronage is limited.

It is difficult at this date to give any adequate statement of the amount of encouragement and active assistance given to Silliman by his scientific colleagues in New Haven and elsewhere—a subject earlier alluded to. It is fortunately possible, however, to acknowledge the generous aid received by the Journal in the early days from a source near at hand. It has already been noted in another place that the dawning activity of science at New Haven was recognized by the founding of the “Connecticut Academy of Arts and Sciences,” formally established at New Haven in 1799 and the third scientific body to be organized in this country. From the beginning of the Journal in 1818, the Connecticut Academy freely gave its support both in papers for publication and at least on one occasion later it gave important financial aid. Upon the occasion of the celebration of the centennial anniversary of the Academy on October 11, 1899, Professor, later Governor, Baldwin, the president of the Academy, discusses this subject in some detail. He says in part:

To support his [Silliman’s] undertaking, a vote had been passed in February [1818], “that the Committee of Publication may allow such of the Academy’s papers as they think proper, to be published in Mr. Silliman’s Scientific Journal.”

Free use was made of this authority, and a large part of the contents of the Journal was for many years drawn from this source. In some cases this fact was noted in publication;[^[2]] but in most it was not....

In 1826, when the Journal was in great need of financial support, the Academy further voted to pay for a year the cost of printing such of its papers as might be published in it. In Baldwin’s Annals of Yale College, published in 1831, it is described as a publication “honorable to the science of our common country,” and having “an additional value as being adopted as the acknowledged organ of the Connecticut Academy of Arts and Sciences.”

Many active campaigns were carried on over the country through paid agents to obtain new subscribers for the Journal and it was doubtless due to these efforts that the nominal subscription list was, at times, as already noted, relatively large as compared with that of a later date. The new subscribers in many cases, however, did not remain permanently interested, often failed to pay their bills, and the uncertain and varying demand upon the supply of printed copies was doubtless one reason why many single numbers became early out of print.

An interesting sidelight is thrown upon the efforts of Silliman to interest the public in his work, at its beginning, by a letter to the editor from Thomas Jefferson, then seventy-five years of age. The writer is indebted to Mr. Robert B. Adam of Buffalo for a copy of this letter and its interest justifies its being reproduced here entire. The letter is as follows:

Monticello, Apr. 11. ’18.

Sir

The unlucky displacement of your letter of Mar 3 has been the cause of delay in my answer. altho’ I have very generally withdrawn from subscribing to or reading periodical publications from the love of rest which age produces, yet I willingly subscribe to the journal you propose from a confidence that the talent with which it will be edited will entitle it to attention among the things of select reading for which alone I have time now left. be so good as to send it by mail, and the receipt of the 1st number will be considered as announcing that the work is commenced and the subscription money for a year shall be forwarded. Accept the assurance of my great esteem and respect.

Th. Jefferson

Professor Silliman.

Contributors.—An interesting summary is also given by Silliman of the contributors to the Journal and the extent of their work (vol. 50, pp. xii, xiii); he says:

We find that there have been about 600 contributors of original matter to the Journal, and we have the unexpected satisfaction of believing that probably five-sixths of them are still living; for we are not certain that more than fifty are among the dead; of perhaps fifty more we are without information, and if that additional number is to be enrolled among the “stelligeri,” we have still 500 remaining. Among them are not a few of the veterans with whom we began our career, and several of these are still active contributors. Shall we then conclude that the peaceful pursuits of knowledge are favorable to long life? This we think is, cœteris paribus, certainly true: but in the present instance, another reason can be assigned for the large amount of survivorship. As the Journal has advanced and death has removed its scientific contributors, younger men and men still younger, have recruited the ranks, and volunteers have enlisted in numbers constantly increasing, so that the flower of the host are now in the morning and meridian of life.

We have been constantly advancing, like a traveller from the equinoctial towards the colder zones,—as we have increased our latitude, stars have set and new stars have risen, while a few planetary orbs visible in every zone, have continued to cheer us on our course.

The number of articles, almost exclusively original, contained in the Journal is about 1800, and the Index will show how many have been contributed by each individual; we have doubtless included in this number some few articles republished from foreign Journals—but we think they are even more than counterbalanced by original communications without a name and by editorial articles, both of which have been generally omitted in the enumeration.

Of smaller articles and notices in the Miscellany, we have not made any enumeration, but they evidently are more numerous than the regular articles, and we presume that they may amount to at least 2500.

Of party, either in politics or religion, there is no trace in our work; of personalities there are none, except those that relate to priority of claims or other rights of individuals. Of these vindications the number is not great, and we could heartily have wished that there had been no occasion for any.

General Scope of Articles.—Many references will be found in the chapters following which throw light upon the character and scope of the papers published in the Journal, particularly in its early years; a few additional statements here may, however, prove of interest.

One feature that is especially noticeable is the frequent publication of articles planned to place before the readers of the Journal in full detail subjects to which they might not otherwise have access. These are sometimes translations; sometimes republications of articles that had already appeared in English periodicals; again, they are exhaustive and critical reviews of important memoirs or books. The value of this feature in the early history of the Journal, when the distribution of scientific literature had nothing of the thoroughness characteristic of recent years, is sufficiently obvious.

It is also interesting to note the long articles of geological description and others giving lists of mineral or botanical localities. Noteworthy, too, is the attempt to keep abreast of occurring phenomena as in the many notes on tornadoes and storms by Redfield, Loomis, etc.; on auroras at different localities; on shooting stars by Herrick, Olmstead and others.

The wide range of topics treated of is quite in accordance with the plan of the editor as given on an earlier page. Some notes, taken more or less at random, may serve to illustrate this point. An extended and quite technical discussion of “Musical Temperament” opens the first number (1, pp. 9–35) and is concluded in the same volume (pp. 176–199). An article on “Mystery” is given by Mark Hopkins, A.M., “late a tutor of Williams College” (13, 217, 1828). There is an essay on “Gypsies” by J. Griscom (from the Revue Encyclopédique) in volume 24 (pp. 342–345, 1833), while some notes on American gypsies are added in vol. 26 (p. 189, 1834). The “divining rod” is described at length in vol. 11 (pp. 201–212, 1826), but without giving any comfort to the credulous; on the contrary the last paragraph states that “the pretensions of diviners are worthless, etc.” A long article by J. Finch on the forts of Boston harbour appeared in 1824 (8, 338–348); the concluding paragraph seems worthy of quotation:

“Many centuries hence, if despotism without, or anarchy within, should cause the republican institutions of America to fade, then these fortresses ought to be destroyed, because they would be a constant reproach to the people; but until that period, they should be preserved as the noblest monuments of liberty.”

The promise to include the fine arts is kept by the publication of various papers, as of the Trumbull paintings (16, 163, 1829); also by a series of articles on “architecture in the United States” (17, 99, 1830; 18, 218, 220, 1830) and others. Quite in another line is the paper by J. W. Gibbs (33, 324, 1838) on “Arabic words in English.” A number of related linguistic papers by the same author are to be found in other volumes. Papers in pure mathematics are also not infrequent, though now not considered as falling within the field of the Journal.

Applied science takes a prominent place through all the volume of the First Series. An interesting paper is that on Eli Whitney, containing an account of the cotton gin; this is accompanied by an excellent portrait (21, 201–264, 1832). The steam engine and its application are repeatedly discussed and in the early volumes brief accounts are given of the early steamboats in use; for example, between Stockholm and St. Petersburg (2, 347, 1820); Trieste and Venice (4, 377, 1822); on the Swiss Lakes (6, 385, 1823). The voyage of the first Atlantic steamboat, the “Savannah,” which crossed from Savannah to Liverpool in 1819, is described (38, 155, 1840); mention is also made of the “first iron boat” (3, 371, 1821; 5, 396, 1822). A number of interesting letters on “Steam Navigation” are given in vol. 35, 160, 162, 332, 333, 336; some of the suggestions seem very quaint, viewed in the light of the experience of to-day.

A very early form of explosive engine is described at length by Samuel Morey (11, 104, 1826); this is an article that deserves mention in these days of gasolene motors. Even more interesting is the description by Charles Griswold (2, 94, 1820) of the first submarine invented by David Bushnell and used in the Revolutionary War in August, 1776. An account is also given of a dirigible balloon that may be fairly regarded as the original ancestor of the Zeppelin (see 11, 346, 1826). The whole subject of aërial navigation is treated at length by H. Strait (25, pp. 25, 26, 1834) and the expression of his hopes for the future deserve quotation:

“Conveyance by air can be easily rendered as safe as by water or land, and more cheap and speedy, while the universal and uniform diffusion of the air over every portion of the earth, will render aërial navigation preferable to any other. To carry it into effect, there needs only an immediate appeal on a sufficiently large scale, to experiment; reason has done her part, when experiment does hers, nature will not refuse to sanction the whole. Aërial navigation will present the works of nature in all their charms; to commerce and the diffusion of knowledge, it will bring the most efficient aid, and it can thus be rendered serviceable to the whole human family.”

A subject of quite another character is the first discussion of the properties of chloroform (chloric ether) and its use as an anæsthetic (Guthrie, 21, 64, 405, 1832; 22, 105, 1832; Levi Ives, 21, 406). Further interesting communications are given of the first analyses of the gastric juice and the part played by it in the process of digestion. Dr. William Beaumont of St. Louis took advantage of a patient who through a gun-shot wound was left with a permanent opening into his stomach through which the gastric juice could be drawn off. The results of Dr. Beaumont and of Professor Robley Dunglison, to whom samples were submitted, are given in full in the life of Beaumont by Jesse S. Myer (St. Louis, 1912). The interest of the matter, so far as the Journal is concerned, is chiefly because Dr. Beaumont selected Professor Silliman as a chemist to whom samples for examination were also submitted. An account of Silliman’s results is given in the Beaumont volume referred to (see also 26, 193, 1834). Desiring the support of a chemist of wider experience in organic analysis, he also sent a sample through the Swedish consul to Berzelius in Stockholm. After some months the sample was received and it is interesting to note in a perfectly fresh condition; it is to be regretted, however, that the Swedish chemist failed to add anything to the results already obtained in this country (27, 40b, 1835).

The above list, which might be greatly extended, seems to leave little ground for the implied criticism replied to by Silliman as follows (16, p. v, 1829):

A celebrated scholar, while himself an editor, advised me, in a letter, to introduce into this Journal as much “readable” matter as possible: and there was, pretty early, an earnest but respectful recommendation in a Philadelphia paper, that Literature, in imitation of the London Quarterly Journal of Science, &c. should be in form, inscribed among the titles of the work.

The Second, Third and Fourth Series.

The Second Series of the Journal, as already stated, began with January, 1846. Up to this time the publication had been a quarterly or two volumes annually of two numbers each. From 1846 until the completion of an additional fifty volumes in 1871, the Journal was made a bimonthly, each of the two yearly volumes having three numbers each. Furthermore, a general index was given for each period of five years, that is for every ten volumes.

Much more important than this change was the addition to the editorial staff of James Dwight Dana, Silliman’s son-in-law. Dana returned from the four-years cruise of the Wilkes Exploring Expedition in 1842; he settled in New Haven, was married in 1844, and in 1850 was appointed Silliman professor of Geology in Yale College. He was at this time actively engaged in writing his three quarto reports for the Expedition and hence did not begin his active professional duties in Yale College until 1856. Part of his inaugural address was quoted on an earlier page.

Dana had already performed the severe labor of preparing the complete index to the First Series, a volume of about 350 pages, finally issued in 1847. From the beginning of the Second Series he was closely associated with his brother-in-law, the younger Silliman. Later the editorial labor devolved more and more upon him and the larger part of this he carried until about 1890. His work, was, however, somewhat interrupted during periods of ill health. This was conspicuously true during a year’s absence in Europe in 1859–60, made necessary in the search for health; during these periods the editorial responsibility rested entirely upon the younger Silliman. Of Dana’s contributions to science in general this is not the place to speak, nor is the present writer the one to dwell in detail upon his work for the Journal. This subject is to such an extent involved in the history of geology and zoology, the subjects of several succeeding chapters, that it is adequately presented in them.

It may, however, be worth stating that in the bibliography accompanying the obituary notice of Dana (49, 329–356, 1895) some 250 titles of articles in the Journal are enumerated; these aggregate approximately 2800 pages. The number of critical notes, abstracts, book reviews, etc., could be also given, were it worth while, but what is much more significant in this connection, than their number or aggregate length, is the fact that these notices are in a large number of cases—like those of Gray in botany—minutely critical and original in matter. They thus give the writer’s own opinion on a multitude of different subjects. It was a great benefit to Dana, as it was to science also, that he had this prompt means at hand of putting before the public the results of his active brain, which continued to work unceasingly even in times of health prostration.

This may be the most convenient place to add that as Dana became gradually less able to carry the burden of the details involved in editing the Journal in addition to his more important scientific labors, particularly from 1890 on, this work devolved more and more upon his son, the present editor, whose name was added to the editorial staff in 1875, with volume 9, of the Third Series. The latter has served continuously until the present time, with the exception of absences, due to ill health, in 1893–94 and in 1903; during the first of these Professor Henry S. Williams and during the second Professor H. E. Gregory occupied the editorial chair.

The Third Series began in 1871, after the completion of the one-hundredth volume from the beginning in 1818. At this date the Journal was made a monthly and as such it remains to-day. Fifty volumes again completed this series, which closed in 1895.

The Fourth Series began with January, 1896, and the present number for July, 1918, is the opening one of the forty-sixth volume or, in other words,—the one hundred and ninety-sixth volume of the entire issue since 1818. The Fourth Series, according to the precedent established, will end with 1920.

Associate Editors.—In 1851 the new policy was introduced of adding “Associate Editors” to the staff. The first of these was Dr. Wolcott Gibbs of Cambridge. He began his duties with the eleventh volume of the Second Series in 1851 and continued them with unceasing care and thoroughness for more than twenty years. In a note dated Jan. 1, 1851 (11, 105), he says:

It is my intention in future to prepare for the columns of this Journal abstracts of the more important physical and chemical memoirs contained in foreign scientific journals, accompanied by references, and by such critical observations as the occasion may demand. Contributions of a similar character from others will of course not be excluded by this arrangement, but I shall hold myself responsible only for those notices which appear over my initials.

The departments covered by Dr. Gibbs, in his excellent monthly contributions, embraced chemistry and physics, and these subjects were carried together until 1873 when they were separated and the physical notes were furnished, first by Alfred M. Mayer and later successively by E. C. Pickering (from 1874), J. P. Cooke (from 1877), and John Trowbridge (from 1880). The first instalment of the long series of notes in chemistry and chemical physics by George F. Barker was printed in volume 50, 1870. He came in at first to occasionally relieve Dr. Gibbs, but soon took the entire responsibility. His name was placed among the associate editors on the cover in 1877 and two years later Dr. Gibbs formally retired. It may be added that from the beginning in 1851 to the present time, the notes in “Chemistry and Physics” have been continued almost without interruption.

The other departments of science have been also fully represented in the notes, abstracts of papers published, book notices, etc., of the successive numbers, but as with the chemistry and physics the subject of botany was long treated in a similar formal manner. For the notes in this department, the Journal was for many years indebted to Dr. Asa Gray, who became associate editor in 1853, two years after Gibbs, although he had been a not infrequent contributor for many years previously. Gray’s contributions were furnished with great regularity and were always critical and original in matter. They formed indeed one of the most valuable features of the Journal for many years; as botanists well appreciate, and, as Professor Goodale has emphasized in his chapter on botany, Gray’s notes are of vital importance in the history of the development of his subject. With Gray’s retirement from active duty, his colleague, George W. Goodale, took up the work in 1888 and in 1895 William G. Farlow, also of Cambridge, was added as an associate editor in cryptogamic botany. At this time, however, and indeed earlier, the sphere of the Journal had unavoidably contracted and botany perforce ceased to occupy the prominent place it had long done in the Journal pages.

This is not the place to present an appreciation of the truly magnificent work of Asa Gray. It may not be out of place, however, to call attention to the notice of Gray written for the Journal by his life-long friend, James D. Dana (35, 181, 1888). The opening paragraph is as follows:

“Our friend and associate, Asa Gray, the eminent botanist of America, the broad-minded student of nature, ended his life of unceasing and fruitful work on the 30th of January last. For thirty-five years he has been one of the editors of this Journal, and for more than fifty years one of its contributors; and through all his communications there is seen the profound and always delighted student, the accomplished writer, the just and genial critic, and as Darwin has well said, ‘The lovable man.’”

The third associate editor, following Gray, was Louis Agassiz, whose work for science, particularly in his adopted home in this country, calls for no praise here. His term of service extended from 1853 to 1866 and, particularly in the earlier years, his contributions were numerous and important. The next gentleman in the list was Waldo I. Burnett, of Boston, who served one year only, and then followed four of Dana’s colleagues in New Haven, of whose generosity and able assistance it would be impossible to say too much. These gentlemen were Brush in mineralogy; Johnson in chemistry, particularly on the agricultural side; Newton in mathematics and astronomy, whose contributions will be spoken of elsewhere; and Verrill—a student of Agassiz—in zoology.

All of these gentlemen, besides their frequent and important original articles, were ever ready not only to give needed advice, but also, to furnish brief communications, abstracts of papers and book reviews, and otherwise to aid in the work. Verrill particularly furnished the Journal a long list of original and important papers, chiefly in systematic zoology, extending from 1865 almost down to the present year. His abstracts and book notices also were numerous and trenchant and it is not too much to say that without him the Journal never could have filled the place in zoology which it so long held. Much later the list of New Haven men was increased by the addition of Henry S. Williams (1894), and O. C. Marsh (1895).

Of the valuable work of those more or less closely associated in the conduct of the Journal at the present time, it would not be appropriate to speak in detail. It must suffice to say that the services rendered freely by them have been invaluable, and to their aid is due a large part of the success of the Journal, especially since the Fourth Series began in 1896. But even this statement is inadequate, for the editor-in-chief has had the generous assistance of other gentlemen, whose names have not been placed on the title page, and who have also played an important part in the conduct of the Journal. This policy, indeed, is not a matter of recent date. Very early in the First Series, Professor Griscom of Paris, as already noted, furnished notes of interesting scientific discoveries abroad. Other gentlemen have from time to time acted in the same capacity. The most prominent of them was Professor Jerome Nicklès of Nancy, France, who regularly furnished a series of valuable notes on varied subjects, chiefly from foreign sources, extending from 1852 to 1869. On the latter date he met an untimely death in his laboratory in connection with experiments upon hydrofluoric acid (47, 434, 1869).

It may be added, further, that one of the striking features about the Journal, especially in the earlier half century of its existence, is the personal nature of many of its contributions, which were very frequently in the form of letters written to Benjamin Silliman or J. D. Dana. This is perhaps but another reflection of the extent to which the growth of the magazine centered around these two men, whose wide acquaintance and broad scientific repute made of the Journal a natural place to record the new and interesting things that were being discovered in science.

The following list gives the names and dates of service, as recorded on the Journal title pages, of the gentlemen formally made Associate Editors:

Wolcott Gibbs	(2)	11, 1851	to	(3)	18, 1879
Asa Gray	„	15, 1853	„	„	34, 1887
Louis Agassiz	„	16, 1853	„	(2)	41, 1866
Waldo I. Burnett	„	16, 1853	„	„	17, 1853
George J. Brush	„	35, 1863	„	(3)	18, 1879
Samuel W. Johnson	„	35, 1863	„	„	18, 1879
Hubert A. Newton	(2)	38, 1864	to	(4)	1, 1896
Addison E. Verrill	„	47, 1869
Alfred M. Mayer	(3)	5, 1873	to	(3)	6, 1873
Edward C. Pickering	„	7, 1874	„	„	13, 1877
George F. Barker	„	14, 1877	„	(4)	29, 1910
Josiah P. Cooke	„	14, 1877	„	(3)	47, 1894
John Trowbridge	(3)	19, 1880
George W. Goodale	„	35, 1888
Henry S. Williams	„	47, 1894
Henry P. Bowditch	„	49, 1895	to	(4)	8, 1899
William G. Farlow	„	49, 1895
Othniel C. Marsh	„	49, 1895	to	(4)	6, 1899
Henry A. Rowland	(4)	1, 1896	„	„	10, 1900
Joseph S. Diller	„	1, 1896
Louis V. Pirsson	„	7, 1899
William M. Davis	„	9, 1900
Joseph S. Ames	„	12, 1901
Horace L. Wells	„	18, 1904
Herbert E. Gregory	„	18, 1904
Horace S. Uhler	„	33, 1912

Present and Future Conditions.

The field to be occupied by the “American Journal of Science and Arts,” as seen by its founder in 1818 and presented by him in the first number, as quoted entire on an earlier page, was as broad as the entire sphere of science itself. It thus included all the departments of both pure and applied science and extended even to music and fine arts also. As the years went by, however, and the practical applications of science greatly increased, technical journals started up, and the necessity of cultivating this constantly expanding field diminished. It was not, however, until January, 1880, that “the Arts” ceased to be a part of the name by which the Journal was known.

About the same date also—or better a little earlier—began an increasing development of scientific research, particularly as fostered by the graduate schools of our prominent universities. The full presentation of this subject would require much space and is indeed unnecessary as the main facts must be distinct in the mind of the reader. It is only right, however, that the large part played in this movement by the Johns Hopkins University (founded in 1876) should be mentioned here.

As a result of this movement, which has been of great benefit in stimulating the growth of science in the country, many new journals of specialized character have come into existence from time to time. Further localization and specialization of scientific publication have resulted from the increased activity of scientific societies and academies at numerous centers and the springing into existence thereby of new organs of publication through them, as also through certain of the Government Departments, the Carnegie Institution, and certain universities and museums.

As bearing upon this subject, the following list of the more prominent scientific periodicals started in this country since 1867 is not without interest:

1867–    . American Naturalist. 1875–    . Botanical Bulletin; later Botanical Gazette. 1879–1913. American Chemical Journal. 1880–1915. School of Mines Quarterly. 1883–    . Science. 1885–    . Journal of Heredity. 1887–    . Journal of Morphology. 1887–1908. Technology Quarterly. 1888–1905. American Geologist. 1891–    . Journal of Comparative Neurology. 1893–    . Journal of Geology. 1893–    . Physical Review. 1895–    . Astrophysical Journal. 1896–    . Journal of Physical Chemistry. 1896–    . Terrestrial Magnetism. 1897–1899. Zoological Bulletin; followed by 1900–    . Biological Bulletin. 1901–    . American Journal of Anatomy. 1904–    . Journal of Experimental Zoology. 1905–    . Economic Geology. 1906–    . Anatomical Record. 1907–    . Journal of Economic Entomology. 1911–    . Journal of Animal Behavior. 1914–    . American Journal of Botany. 1916–    . Genetics. 1918–    . American Journal of Physical Anthropology.

The result of the whole movement has been of necessity to narrow, little by little, the sphere of a general scientific periodical such as the Journal has been from the beginning. The exact change might be studied in detail by tabulating as to subjects the contents of successive volumes, decade by decade, from 1870 down. It is sufficient, here, however, to recognize the general fact that while the number of original papers published in the periodicals of this country, in 1910, for example, was very many times what it was in 1825, a large part of these have naturally found their home in periodicals devoted to the special subject dealt with in each case. That this movement will continue, though in lessened degree now that the immediate demand is measurably satisfied, is to be expected. At the same time it has not seemed wise, at any time in the past, to formally restrict the pages of the Journal to any single group of subjects. The future is before us and its problems will be met as they arise. At the moment, however, there seems to be still a place for a scientific monthly sufficiently broad to include original papers of important general bearing even if special in immediate subject. In this way it would seem that “Silliman’s Journal” can best continue to meet the ideals of its honored founder, modified as they must be to meet the change of conditions which a century of scientific investigation and growth have wrought. Incidentally it is not out of place to add that a self-supporting, non-subsidized scientific periodical may hope to find a larger number of subscribers from among the workers in science and the libraries if it is not too restricted in scope.

The last subject touched upon introduces the essential matter of financial support without which no monthly publication can survive. With respect to the periodicals of recent birth, listed above, it is safe to say that some form of substantial support or subsidy—often very generous—is the rule, perhaps the universal one. This has never been the case with the American Journal. The liberality and broad-minded attitude of Yale College in the early days, and of the Yale University that has developed from it, have never been questioned. At the same time the special conditions have been such as to make it desirable that the responsibility of meeting the financial requirements should be carried by the editors-in-chief. At present the Yale Library gives adequate payment for certain publications received by the Journal in exchange, though for many years they were given to it as a matter of course, free of charge. Beyond this there is nothing approaching a subsidy.

The difficulties on the financial side met with by the elder Silliman have been suggested, although not adequately presented, in the various statements quoted from early volumes. The same problems in varying degree have continued for the past sixty years. Since 1914 they have been seriously aggravated for reasons that need not be enlarged upon. Prior to that date the subscription list had, for reasons chiefly involved in the development of special journals, been much smaller than the number estimated by Silliman, for example, in volume 50 (p. xiv), although there has been this partial compensation that the considerable number of well-established libraries on the subscription list has meant a greater degree of stability and a smaller proportion of bad accounts. The past four years, however, the Journal, with all similar undertakings here and elsewhere, has been compelled to bear its share of the burden of the world war in diminished receipts and greatly increased expenses. It is gratifying to be able to acknowledge here the generosity of the authors, or of the laboratories with which they have been connected, in their willingness not infrequently to give assistance, for example, in the payment of more or less of the cost of engravings, or in a few special cases a large portion of the total cost of publication. In this way the problem of ways and means, constantly before the editor who bears the sole responsibility, has been simplified.

It should also be stated that as those immediately interested have looked forward to the present anniversary, it has been with the hope that this occasion might be an appropriate one for the establishment of a “Silliman Fund” to commemorate the life and work of Benjamin Silliman. The income of such a fund would lift from the University the burden that must unavoidably fall upon it when the responsibility for the conduct of the Journal can no longer be carried by members of the family including the editor and—as in years long past—a silent partner whose aid on the business side has been essential to the efficiency and economy of the enterprise. Present conditions are not favorable for such a movement, although something has been already accomplished in the desired direction. At the present time every patriotic citizen must feel it his first duty to give his savings as well as his spare income to the support of the National Government in the world struggle for freedom in which it is taking part. But, whatever the exact condition of the future may be, it cannot be questioned that the Journal founded by Benjamin Silliman in 1818 will survive and will continue to play a vital part in the support and further development of science.

The present year of 1918 finds the world at large, and with it the world of science, painfully crushed beneath the overwhelming weight of a world war of unprecedented severity. The four terrible years now nearly finished have seen a fearful destruction of life and property which must have a sad influence on the progress of science for many years to come. Only in certain restricted lines has there been a partial compensation in the stimulating influence due to the immediate necessities connected with the great conflict. One hundred years ago “the reign of war” was keenly in the mind of the editor in beginning his work, but for him, happily, the long period of the Napoleonic wars was already in the past, as also the brief conflict of 1812, in which this country was engaged and in which Silliman himself played a minor part. We, too, must believe, no matter how serious the outlook of the present moment, that a fundamental change will come in the not distant future; the nations of the world must sooner or later turn once more to peaceful pursuits and the scientific men of different races must become again not enemies but brothers engaged in the common cause of uplifting human life. The peace that we look forward to to-day is not for this country alone, but a peace which shall be a permanent blessing to the entire world for ages to come.

Note.—The portrait which forms the frontispiece of this volume has been reproduced from the plate in volume 50 (1847). The original painting was made by H. Willard in 1835, when Silliman was in Boston engaged in delivering the Lowell lectures; he was then nearly fifty-six years of age. The engraving, as he states elsewhere, was made from this painting for the Yale Literary Magazine, and was published in the number for December, 1839.

It is interesting to quote the remarks with which the editor introduces the portrait (50, xviii, 1847). He says:

The portrait prefixed to this volume was engraved for a very different purpose and for others than the patrons of this Journal. It has been suggested by friends, whose judgment we are accustomed to respect, that it ought to find a place here, since it is regarded as an authentic, although, perhaps, a rather austere resemblance. In yielding to this suggestion, it may be sufficient to quote the sentiment of Cowper on a similar occasion, who remarked—“that after a man has, for many years, turned his mind inside out before the world, it is only affectation to attempt to hide his face.”

Notes.

[1]. The statements given are necessarily much condensed, without an attempt to follow all changes of title; furthermore, the dates of actual publication for the academies given above are often somewhat vaguely recorded. For fuller information see Scudder’s “Catalogue of Scientific Serials, 1633–1876,” Cambridge, 1876; also H. Carrington Bolton’s “Catalogue of Scientific and Technical Periodicals, 1665–1882” (Smithsonian Institution, 1885). The writer is much indebted to Mr. C. J. Barr, Assistant Librarian of Yale University Library, for his valuable assistance in this connection.

[2]. The following footnote accompanies the opening article of the first volume of the Journal. “From the MS. papers of the Connecticut Academy, now published by permission.” Similar notes appear elsewhere. Ed.

II
A CENTURY OF GEOLOGY.—THE PROGRESS OF HISTORICAL GEOLOGY IN NORTH AMERICA

By CHARLES SCHUCHERT

Introduction.

The American Journal of Science, “one of the greatest influences in American geology,” founded in 1818, has published a little more than 92,000 pages of scientific matter. Of geology, including mineralogy, there appear to be upward of 20,000 pages. What a vast treasure house of geologic knowledge is stored in these 194 volumes, and how well the editors have lived up to their proposed “plan of work” as stated in the opening volume, where Silliman says: “It is designed as a deposit for original American communications” in “the physical sciences ... and especially our mineralogy and geology” (1, v, 1818)! Not only is it the oldest continuously published scientific journal of this country, but it has proved itself to be “perhaps the most important geological periodical in America” (Merrill). It is impossible to adequately present in this memorial volume of the Journal the contents of the articles on the geological sciences.

Editor Silliman was not only the founder of the Journal, but the generating center for the making of geologists and promoting geology during the rise of this science in America. For nearly three decades, the workers came to him for counsel and help, and he had a kind paternal word for them all. This influence is also shown in the many letters which were addressed to him, and which he published in the Journal. A similar influence, paternal care, and constructive criticism were continued by James D. Dana, and especially in his earlier career as editor.

Not including mineralogy, there are in the Journal upward of 1500 distinct articles on geology. Of these, over 400 are on vertebrate paleontology, about 325 on invertebrate paleontology, and 90 on paleobotany. Of articles bearing on historical geology there are about 160, and on stratigraphic geology more than 360. In addition to all this, there are more than 2000 pages of geologic matter relating to books and of letters communicated to the editors Silliman and Dana. We may summarize with Doctor Merrill’s statement in his well-known Contributions to the History of American Geology:

“From its earliest inception geological notes and papers occupied a prominent place in its pages, and a perusal of the numbers from the date of issue down to the present time will, alone, afford a fair idea of the gradual progress of American geology.”

Before presenting a synopsis of the more important steps in the progress of historical geology in America, it will be well to introduce a rapid survey of the rise of geology in Europe, for, after all, American geology grew out of that of England, France and Germany. This dependence was conspicuously true during the first four decades of the previous century. With the rise of the first New York State Survey (1836–1843) and that of Pennsylvania (1836–1844, 1858), American geology became more or less independent of Europe. Finally, this article will conclude with a survey of the rise of paleometeorology, paleogeography, evolution, and invertebrate paleontology.

The Rise of Geology in Europe.

Mineral Geology.—The geological sciences had their rise in the study of minerals as carried on by the German chemist and physician George Bauer (1494–1555), better known as Agricola. Bauer originated the critical study of minerals, but did not distinguish his “fossilia,” the remains of organisms, from the inorganic crystal forms. Mineral geology endured until the close of the eighteenth century.

Cosmogonists.—Then came the expounders of the earth’s origin, the cosmogonists of the sixteenth to the end of the eighteenth centuries. The fashion of this time was to write histories of the earth derived out of the imagination.

Earliest Historical Geology.—Even though Giovanni Arduino (1713–1795) of Padua was not the first to classify the rocks into three series according to their age, he did this more clearly than any one else before his time. The rocks about Verona he grouped in 1759 into Primary, Secondary, Tertiary, and Volcanic. This three-fold classification came into general use, though modified with time.

Early in the nineteenth century it had become plain that formations of very varying ages were included in each one of the three series. Through the study of the fossils and the recognition of the fact that mountain ranges have been raised at various times, causing younger fossiliferous strata to take on the characters of the Primary, it was seen that these terms of Arduino had lost their original significance.

The first one to describe in detail a local stratigraphic sequence was Johann Gottlob Lehmann (died 1767). In 1756 he published “one of the classics of geological literature,” distinguishing clearly thirty successive sedimentary deposits, some of which he said had fossils, but he did not use them to distinguish the strata.

What Lehmann did for the Permian system, George Christian Füchsel (1722–1773) did even better for the Triassic of Thuringia, in 1762 and 1773. He pointed out not only the sequence, but also how the gently inclined strata rest upon the older upturned masses of the mountains; also that some formations have only marine fossils, while others have only terrestrial forms and thus indicate the proximity of land. The deformed strata he thought had fallen into the hollows within the earth, great caverns that had also consumed much of the oceanic waters and had in so doing greatly lowered the sea-level. It was Füchsel who first introduced the theory of universal formations, and who defined the term formation, using it as we now do, system or period. Even though Lehmann and Füchsel showed that there was a definite order and process in the formation of the earth’s crust, their example was barren of followers until the beginning of the eighteenth century.

Wernerian Geology or Geognosy.—We come now to the time of Abraham Gottlob Werner (1749–1817), who from 1775 to 1817 was professor of mining and mineralogy in the Freiberg Academy of Mines. Geikie, in his most interesting Founders of Geology, says that Werner “bulks far more largely in the history of geology than any of those with whom up to the present we have been concerned—a man who wielded an enormous authority over the mineralogy and geology of his day.” “Although he did great service by the precision of his lithological characters and by his insistence on the doctrine of geological succession, yet as regards geological theory, whether directly by his own teaching, or indirectly by the labors of his pupils and followers, much of his influence was disastrous to the higher interests of geology.”

Werner arranged the crust of the earth into a series of formations, as had been done previously by Lehmann and Füchsel, and one of his fundamental postulates was that all rocks were chemically precipitated in the ocean as “universal formations.” For this reason Werner’s school were called the Neptunists. Nowhere, however, did he explain how and where the deep and primitive ocean had disappeared.

According to Werner, the first formed or oldest rocks were the chemically deposited Primitive strata, including granite and other igneous and metamorphic rocks. On these followed the Transition rocks, the earliest sediments of mechanical origin, and above them the Floetz rocks, a term for the horizontal stratified rocks. These last he said were partly of chemical but chiefly of mechanical origin. Last of all came the Alluvial series.

The existence of volcanoes had been pointed out long before Werner’s time by the Italian school of geologists, but as for “the universality and potency of what is now termed igneous action,” all was “brushed aside by the oracle of Freiberg.” Reactions between the interior and exterior of our earth “were utterly antagonistic to Werner’s conception of the structure and history of the earth.” To him, volcanoes were “burning mountains” that arose from the combustion of subterranean beds of coal, spontaneously ignited.

The breaking down of the Wernerian doctrines began with two of Werner’s most distinguished pupils, D’Aubuisson de Voisins (1769–1819) and Von Buch. The former in 1803 had accepted Werner’s aqueous origin of basalt, but after studying the celebrated and quite recent volcanic area of Auvergne he recanted in 1804. Here he saw the basaltic rocks lying upon and cutting through granite, and in places more than 1200 feet thick. “If these basaltic rocks were lavas,” says Geikie, “they must, according to the Wernerian doctrine, have resulted from the combustion of beds of coal. But how could coal be supposed to exist under granite, which was the first chemical precipitate of a primeval ocean?”

Leopold von Buch (1774–1853), “the most illustrious geologist that Germany has produced,” after two years spent in Norway was satisfied “that the rocks in the Christiania district could not be arranged according to the Wernerian plan, which there completely broke down. Von Buch found a mass of granite lying among fossiliferous limestones which were manifestly metamorphosed, and were pierced by veins of granite, porphyry, and syenite.” Even so, he was not ready to abandon the teachings of his master. After a study of the mountain systems of Germany, however, “he declared that the more elevated mountains had never been covered by the sea, as Werner had taught, but were produced by successive ruptures and uplifts of the terrestrial crust” (Geikie).

Rise of Geology and Conformism.—Modern geology has its rise in James Hutton (1726–1797) of Edinburgh, Scotland. In 1785 and 1795, Hutton published his Theory of the Earth, with Proofs and Illustrations. His “immortal theory” is his only work on geology. “Fortunately for Hutton’s fame and for the onward march of geology, the philosopher numbered among his friends the illustrious mathematician and natural philosopher, John Playfair (1748–1819), who had been closely associated with him in his later years, and was intimately conversant with his geological opinions.” In 1802, Playfair published his Illustrations of the Huttonian Theory of the Earth, of which Geikie says, “Of this great classic it is impossible to speak too highly,” as it is at the basis of all modern geology.

One of Hutton’s fundamental doctrines is that the earth is internally hot and that in the past large masses of molten material, the granites, have been intruded into the crust. It was these igneous views that led to his followers being called the Plutonists. Another of his great doctrines was that “the ruins of an earlier world lie beneath the secondary strata,” and that they are separated by what is now known as unconformity. He clearly recognized a lost interval in the broken relation of the structures, and that the ruins, the detrital materials, of one world after another are superposed in the structure of the earth.

Hutton also held that the deformation of once horizontally deposited strata was probably brought about at different periods by great convulsions that shook the very foundations of the earth. After a convulsion, there was a long time of erosion, represented by the unconformity. Geikie says, “The whole of the modern doctrine of earth sculpture is to be found in the Huttonian theory.”

The Lyellian doctrine of metamorphism had its origin in Hutton, for he showed that invading igneous granite had altered, through its heat and expanding power, the originally waterlaid sediments, and that the schists of the Alps had been born of the sea like other stratified rocks.

Hutton is the father of the Uniformitarian principle, for he “started with the grand conception that the past history of our globe must be explained by what can be seen to be happening now, or to have happened only recently. The dominant idea in his philosophy is that the present is the key to the past.” This principle has been impressed on all later geologists by Sir Charles Lyell, and is the chief cornerstone of modern geology.

The principle of uniformitarianism has underlain geologic interpretation since the days of Hutton, Playfair, and Lyell. However, it is often applied too rigidly in interpretations based upon the present conditions, because in the past there were long times when the topographic features of the earth were very different from those of to-day. Throughout the Paleozoic, and, less markedly, the Mesozoic, the oceans flooded the lands widely (at times over 60 per cent of the total area), highlands were inconspicuous, sediments far scarcer, and climates warm and equable throughout the world. Highland conditions, and especially the broadly emergent continents of the present, were only periodically present in the Paleozoic and then for comparatively short intervals between the periods. Therefore rates of denudation, solution, sedimentation, and evolution have varied greatly throughout the geological ages. These differences, however, relate to degrees of operation, and not to kinds of processes; but the differences in degree of operation react mightily on our views as to the age of the earth.

Geologic time had, for Hutton, no “vestige of a beginning, no prospect of an end.” In other words, geologic time is infinite. He did not, however, discover a method by which the chronology of the earth could be determined.

First Important Text-books.—In 1822 appeared the ablest text-book so far published, and the pattern for most of the later ones, Outlines of the Geology of England and Wales, by W. D. Conybeare (1787–1857) and W. Phillips (1775–1828). “In this excellent volume all that was then known regarding the rocks of the country, from the youngest formations down to the Old Red Sandstone, was summarized in so clear and methodical a manner as to give a powerful impulse to the cultivation of geology in England” (Geikie). This book is reviewed at great length by Edward Hitchcock in the Journal (7, 203, 1824).

To indicate how far historical geology had progressed up to 1822 in England, a digest of the geological column as presented in this text-book is given in the following table, along with other information.

A text-book writer of yet greater influence was Charles Lyell (1797–1875), whose Principles of Geology appeared in three volumes between 1830 and 1833. This and his other books were kept up to date through many editions, and his Elements of Geology is, as Geikie says, “the hand book of every English geologist” working with the fossiliferous formations.

The Rise of Geology in North America.

The Generating Centers.—In America, geology had its rise independently in three places: in the two scientific societies of Boston and Philadelphia, and dominantly in Benjamin Silliman of Yale College. Stated in another way, we may say that geology in America had its origin in the following pioneers and founders: first, in William Maclure at Philadelphia, and next in Benjamin Silliman at New Haven. Through the influence of the latter, Amos Eaton, the botanist, became a geologist and taught geology at Williams College and later at the Rensselaer School in Troy, New York. Through the same influence Rev. Edward Hitchcock also became a geologist and taught the subject after 1825 at Amherst College.

Silliman was the first to take up actively the teaching of mineralogy and geology based on collections of specimens. He spread the knowledge in popular lectures throughout the Eastern States, graduated many a student in the sciences, making of some of them professional teachers and geologists, provided all with a journal wherein they could publish their research, organized the first geological society and through his students the first official geological surveys, and by kind words and acts stimulated, fostered, and held together American scientific men for fifty years. Of him it has been truly said that he was “the guardian of American science from its childhood.”

The American Academy in Boston.—The second oldest scientific society, but the first one to publish on geological subjects, was the American Academy of Arts and Sciences of Boston, instituted and publishing since 1780. Up to the time of the founding of this Journal, there had appeared in the publications of the American Academy about a dozen papers of a geologic character, none of which need to be mentioned here excepting one by S. L. and J. F. Dana, entitled “Outlines of the Mineralogy and Geology of Boston,” published in 1818. This is an early and important step in the elucidation of one of the most intricate geologic areas, and is further noteworthy for its geologic map, the third one to appear, the older ones being by Maclure and Hitchcock (Merrill).

The Geological Column in 1822
Present American classification			Conybeare and Phillips 1822	C. & P. orders	Wernerian orders	Other writers
Psychozoic or Recent			Alluvial	Superior Order	Newest Floetz Class	Tertiary Class
Cenozoic	Pleistocene		Diluvial
	Pliocene	Neogene	Upper Marine formation (Crag, Bagshot sand, and Isle of Wight)
	Miocene
			Fresh-water formations
	Oligocene	Paleogene	London Clay
	Eocene		Plastic Clay
Mesozoic	Cretaceous		Chalk	Supermedial Order	Primitive Transition and Floetz Classes	Primitive Intermediate and Secondary classes
	Comanchian 1887		Beds between Chalk and Oolite Series (Chalk Marle, Green Sand, Weald Clay, Iron Sand)
	Jurassic 1829		Upper Oolitic division (Purbeck beds, Portland Oolite, Kimmeridge Clay)
			Middle Oolitic division (Coral Rag, Oxford Clay)
			Lower Oolitic division (Cornbrash Stonesfield Slate, Forest Marble, Great Oolite, Fullers’ Earth, Inferior Oolite, Sand and Marlestone)
			Lias
	Triassic 1834		New Red Sandstone
Paleozoic	Permian 1841		Magnesian Limestone
			Coal Measures	Medial or Carboniferous Order
	Pennsylvanian 1891
	Mississippian 1869		Millstone Grit and Shale
			Old Red Sandstone
	Devonian 1839
	Silurian 1835		Unresolved Submedial and Inferior Orders
	Ordovician 1879
	(=Lower Silurian 1835)
	Cambrian 1833
Proterozoic	Keweenawan	Huronian 1852
	Animikian
	Huronian
	Sudburian
Archeozoic	Keewatin	Laurentian 1853
	Coutchiching

Early Geology in Philadelphia.—The oldest scientific society is the American Philosophical Society of Philadelphia, started by the many-sided Benjamin Franklin in 1769, and which has published since 1771. Up to the time of the founding of the Journal in 1818, there had appeared in the publications of this society thirteen papers of a geologic nature, nearly all small building stones in the rising geologic story of North America. The only fundamental ones were Maclure’s Observations of 1809 and 1817. Later, in this same city, there was organized another scientific society that came to be for a long time the most active one in America. This was the Academy of Natural Sciences, started in 1812 with seven members, but it was not until 1817 and the election of William Maclure as its first president that the work of the Academy was of a far-reaching character. Here was built up not only a society for the advancement of the natural sciences and publications for the dissemination of such knowledge, but, what is equally important, the first large library and general museum.

William Maclure (1763–1840), correctly named by Silliman the “father of American geology,” was born and educated in Scotland, and died near Mexico City. A merchant of London until 1796, when he had already amassed “a considerable fortune,” he made a first short visit to New York City in 1782. In 1796 he again came to America, this time to become a citizen of this country and a liberal patron of science.

About 1803, single-handed and unsustained by government patronage, Maclure interested himself most zealously and efficiently in American geology. In 1809 he published his Observations on the Geology of the United States, Explanatory of a Geological Map. This work he revised “on a yet more extended scale,” issuing it in 1817 with 130 pages of text, accompanied by a large colored geological map.

Silliman, the Pioneer Promoter of Geology.—In 1806 when Benjamin Silliman (1779–1864) began actively to teach chemistry and mineralogy, all the sciences in America were in a very backward state, and the earth sciences were not recognized as such in the curricula of any of our colleges. Silliman gave his first lecture in chemistry on April 4, 1804. In the summer of that year, Yale College asked him to go to England to purchase material for the College, and great possibilities for broadening his knowledge now loomed before him. As Silliman himself (43, 225, 1842) has told the interesting story of his sojourn in England and Scotland, it is worth while to restate a part of it here.

“Passing over to England in the spring of 1805, and fixing my residence for six months in London, I found there no school, public or private, for geological instruction, and no association for the cultivation of the science, which was not even named in the English universities.” In geology “Edinburgh was then far in advance of London.... Prof. Jameson having recently returned from the school of Werner, fully instructed in the doctrines of his illustrious teacher, was ardently engaged to maintain them, and his eloquent and acute friend, the late Dr. John Murray, was a powerful auxiliary in the same cause; both of these philosophers strenuously maintaining the ascendancy of the aqueous over the igneous agencies, in the geological phenomena of our planet.

On the other hand, the disciples and friends of Dr. Hutton were not less active. He died in 1797, and his mantle fell upon Sir James Hall, who, with Prof. Playfair and Prof. Thomas Hope, maintained with signal ability, the igneous theory of Hutton. It did not become one who was still a youth and a novice, to enter the arena of the geological tournament where such powerful champions waged war; but it was very interesting to view the combat, well sustained as it was on both sides, and protracted, without a decisive issue, into a drawn battle....

The conflicts of the rival schools of Edinburgh—the Neptunists and the Vulcanists, the Wernerians and the Huttonians, were sustained with great zeal, energy, talent, and science; they were indeed marked too decidedly by a partisan spirit, but this very spirit excited untiring activity in discovering, arranging, and criticising the facts of geology. It was a transition period between the epoch of geological hypotheses and dreams, which had passed by, and the era of strict philosophical induction, in which the geologists of the present day are trained....

I was a diligent and delighted listener to the discussions of both schools. Still the igneous philosophers appeared to me to assume more than had been proved regarding internal heat. In imagination we were plunged into a fiery Phlegethon, and I was glad to find relief in the cold bath of the Wernerian ocean, where my predilections inclined me to linger.”

Silliman’s Students and Their Publications.—Silliman’s first student to take up geology as a profession was Denison Olmstead (1791–1859), educator, chemist, and geologist, who was graduated from Yale in 1813. Four years later he was under special preparation with Silliman in mineralogy and geology, and in that year was appointed professor of chemistry in the University of North Carolina. In 1824–1825 Olmstead issued a Report on the Geology of North Carolina, which is the first official geological report issued by any state in America, “a conspicuous and solitary instance,” according to Hitchcock’s review of it (14, 230, 1828), “in which any of our state governments have undertaken thoroughly to develop their mineral resources.”

Amos Eaton (1776–1842), lawyer, botanist, surveyor, and one of the founders of American geology, was a graduate of Williams College in the class of 1799. He studied with Silliman in 1815, attending his lectures on chemistry, geology, and mineralogy. He also enjoyed access to the libraries of Silliman and of the botanist, Levi Ives, in which works on botany and materia medica were prominent, and was a diligent student of the College cabinet of minerals. He settled as a lawyer and land agent in Catskill, New York, and here in 1810 he gave a popular course of lectures on botany, believed to have been the first attempted in the United States.

In 1818 appeared Eaton’s first noteworthy geological publication, the Index to the Geology of the Northern States, a text-book for the classes in geology at Williamstown. The controlling principle of this book was Wernerism, a false doctrine from which Eaton was never able to free himself. This book was “written over anew” and published in 1820.

While at Albany in 1818, Governor De Witt Clinton asked Eaton to deliver a course of lectures on chemistry and geology before the members of the legislature of New York. It is believed that Eaton is the only American having this distinction, and because of it he became acquainted with many leading men of the state, interesting them in geology and its application to agriculture by means of surveys. In this way was sown the idea which eventually was to fructify in that great official work: The Natural History of New York. (See 43, 215, 1842; and Youmans’ sketch of Eaton’s life, Pop. Sci. Monthly, Nov. 1890.)

Edward Hitchcock (1793–1864), reverend, state geologist, college president, and another of the founders of American geology, was largely self-taught. Previous to 1825, when he entered the theological department of Yale College, he had met Amos Eaton, who interested him in botany and mineralogy, and between 1815 and 1819 he had made lists of the plants and minerals found about his native town, Deerfield, Massachusetts. Therefore, while studying theology at Yale it was natural for him also to take up mineralogy and geology with Silliman, whose acquaintance he had made at least as early as 1818.

Hitchcock, who was destined to be one of the most prominent figures of his time, was appointed in 1825 to the chair of chemistry and natural history at Amherst College. His first geologic paper, one of five pages, appeared in 1815. Three years later appeared his more important paper on the Geology and Mineralogy of a Section of Massachusetts, New Hampshire, and Vermont (1, 105, 436, 1818). This is also noteworthy for its geological map, the next one to be published after those of Maclure of 1809 and 1817. In 1823 came a still greater work, A Sketch of the Geology, Mineralogy, and Scenery of the Regions contiguous to the River Connecticut (6, 1, 200, 1823; 7, 1, 1824). Here the map above referred to was greatly improved, and the survey was one of the most important of the older publications.

Youmans in his account of Hitchcock (Pop. Sci. Monthly, Sept. 1895) says:

“The State of Massachusetts commissioned him to make a geological survey of her territory in 1830. Three years were spent in the explorations, and the work was of such a high character that other States were induced to follow the example of Massachusetts.... The State of New York sought his advice in the organization of a survey, and followed his suggestions, particularly in the division of the territory into four parts, and appointed him as the geologist of the first district. He entered upon the work, but after a few days of labor he found that he must necessarily be separated from his family, much to his disinclination. He also conceived the idea of urging a more thorough survey of his own State; hence he resigned his commission and returned home. The effort for a resurvey of Massachusetts was successful, and he was recommissioned to do the work. The results appeared in 1841 and 1844.”

Oliver P. Hubbard was assistant to Silliman in 1831–1836, and then up to 1866 taught chemistry, mineralogy, and geology at Dartmouth College. James G. Percival was graduated at Yale in 1815, and in 1835 he and C. U. Shepard of Amherst College were appointed state geologists of Connecticut. Their report was issued in 1842.

James Dwight Dana (1813–1895) was undoubtedly the ablest of all of Silliman’s students. Graduated at Yale in 1833, he spent fifteen months in the United States Navy as instructor in mathematics, cruising off France, Italy, Greece, and Turkey. In 1836 he was assistant to Silliman, and in 1837, at the age of twenty-four years, he published his widely used System of Mineralogy. Two years later Dana joined the Wilkes Exploring Expedition as mineralogist, returning to America in 1842; his geological results of this expedition were published in 1849. In 1863, during the Rebellion, he published his Manual of Geology, and through four editions it remained for forty years the standard text-book for American geologists.

First American Geological Society.—The founding in 1807 of the Geological Society of London, the parent of geological societies, undoubtedly had its stimulating effect on Silliman, and with his marked organizing ability he began to think of forming an American society of the same kind. This he brought about the year following the appearance of the Journal, that is, in 1819. The American Geological Society, begun in 1819 (1, 442, 1819), was terminated in 1830 (17, 202, 1830). The first meeting (September 6, 1819) and all the subsequent ones were held in the cabinet of Yale College. The brief records of the doings of this society are printed in volumes 1, 10, 15, and 18 of the Journal. Silliman was the attraction at the meetings, surrounded by his mineral cabinet, and he gave “the true scientific dress to all the naked mineralogical subjects” discussed.

Wernerian Geology in North America.

The Father of American Geology.—Historical Geology begins in America with William Maclure’s Observations on the Geology of the United States, issued in 1809. This was the first important original work on North American geology, and its colored geological map was the first one of the area east of the Mississippi River. The classification was essentially the Wernerian system. All of the strata of the Coastal Plain, now known to range from the Lower Cretaceous to Recent, were referred to the Alluvial. To the west, over the area of the Piedmont, were his Primitive rocks, while the older Paleozoic formations of the Appalachian ranges were referred to the Transition. West of the folded area, all was Floetz or Secondary, or what we now know as Paleozoic sedimentaries. The Triassic of the Piedmont area and that of Connecticut he called the Old Red Sandstone, and the coal formations of the interior region he said rested upon the Secondary. The second edition of the work in 1817 was much improved, along with the map, which was also printed on a more correct geographic base. (For greater detail, see Merrill, Contributions to the History of American Geology, 1906.)

Even though Maclure’s geologic maps are much generalized, and the scheme of classification adopted a very broad one, they are in the main correct, even if they do emphasize unduly the rather simple geologic structure of North America. This fact is patent all through Maclure’s description. Cleaveland also refers to it in his treatise of 1816, and Silliman in the opening volume of the Journal (1, 7, 1818) says: “The outlines of American geology appear to be particularly grand, simple, and instructive.” Then, all the kinds of rocks were comprehended under four classes, Primitive, Transition, Alluvial, and Volcanic. It is also interesting to note here that in 1822 Maclure had lost faith in the aqueous origin of the igneous rocks and writes of the Wernerian system as “fast going out of fashion” (5, 197, 1822), while Hitchcock said about the same thing in 1825 (9, 146).

The Work of Eaton.—Amos Eaton, after traveling 10,000 miles and completing his Erie Canal Report in 1824, “reviewed the whole line several times,” and published in 1828 in the Journal (14, 145) a paper on Geological Nomenclature, Classes of Rocks, etc. The broader classification is the Wernerian one of Primitive, Transition, and Secondary classes. Under the first two he has fossiliferous early Paleozoic formations, but does not know it, because he pays no attention anywhere to the detail of the entombed fossils, and all of his Secondary is what we now call Paleozoic. The correlations of the latter are faulty throughout.

Then came his paper of 1830, Geological Prodromus (17, 63), in which he says: “I intend to demonstrate ... that all geological strata are arranged in five analogous series; and that each series consists of three formations; viz., the Carboniferous [meaning mud-stones], Quartzose, and Calcareous.” We seem to see here expressed for the first time the idea of “cycles of sedimentation,” but Eaton does not emphasize this idea, and the localities given for each “formation” of “analogous series” demonstrate beyond a doubt that he did not have a sedimentary sequence. The whole is simply a jumble of unrelated formations that happen to agree more or less in their physical characters.

“I intend to demonstrate,” he says further, “that the detritus of New Jersey, embracing the marle, which contains those remarkable fossil relics, is antediluvial, or the genuine Tertiary formation.” This correlation had been clearly shown by Finch in 1824 (7, 31) and yet both are in error in that they do not distinguish the included Cretaceous marls and greensands as something apart from the Tertiary.

One gets impatient with the later writings of Eaton, because he does not become liberalized with the progressive ideas in stratigraphic geology developing first in Europe and then in America, especially among the geologists of Philadelphia. Therefore it is not profitable to follow his work further.

Early American Text-books of Geology.—The first American text-book of geology bears the date of Boston 1816 and is entitled An Elementary Treatise on Mineralogy and Geology, its author being Parker Cleaveland of Bowdoin College. The second edition appeared in 1822. It also had a geologic map of the United States, practically a copy of Maclure’s. To mineralogy were devoted 585 pages, and to geology 55, of which 37 describe rocks and 5 the geology of the United States. The chronology is Wernerian. Of “geological systems” there are two, “primitive and secondary rocks.”

In 1818 appeared Amos Eaton’s Index to the Geology of the Northern States, having 54 pages, and in 1820 came the second edition, “wholly written over anew,” with 286 pages. The theory of the later edition is still that of Werner, with “improvements of Cuvier and Bakewell,” and yet one sees now-a-days but little in it of the far better English text-book. Eaton did very little to advance philosophic geology in America. What is of most value here are his personal observations in regard to the local geology of western Massachusetts, Connecticut, southwestern Vermont, and eastern New York (1, 69, 1819; also Merrill, p. 234).

We come now to the most comprehensive and advanced of the early text-books used in America. This is the third English edition of Robert Bakewell’s Introduction to Geology (400 pages, 1829), and the first American edition “with an Appendix Containing an Outline of his Course of Lectures on Geology at Yale College, by Benjamin Silliman” (128 pages). Bakewell’s good book is in keeping with the time, and while not so advanced as Conybeare and Phillips’s Outlines of 1822, yet is far more so than Silliman’s appendix. The latter is general and not specific as to details; it is still decidedly Wernerian, though in a modified form. Silliman says he is “neither Wernerian nor Huttonian,” and yet his summary on pages 120 to 126 shows clearly that he was not only a Wernerian but a pietist as well.

Unearthing of the Cenozoic and Mesozoic in North America.

The Discerning of the Tertiary.—The New England States, with their essentially igneous and metamorphic formations, could not furnish the proper geologic environment for the development of stratigraphers and paleontologists. So in America we see the rise of such geologists first in Philadelphia, where they had easy access to the horizontal and highly fossiliferous strata of the coastal plain. The first one to attract attention was Thomas Say, after him came John Finch, followed by Lardner Vanuxem, Isaac Lea, Samuel G. Morton, and T. A. Conrad. These men not only worked out the succession of the Cenozoic and the upper part of the Mesozoic, but blazed the way among the Paleozoic strata as well.

Thomas Say (1787–1834), in 1819, was the first American to point out the chronogenetic value of fossils in his article, Observations on some Species of Zoophytes, Shells, etc., principally Fossil (1, 381). He correctly states that the progress of geology “must be in part founded on a knowledge of the different genera and species of reliquiæ, which the various accessible strata of the earth present.” Say fully realizes the difficulties in the study of fossils, because of their fragmental character and changed nature, and that their correct interpretation requires a knowledge of similar living organisms.

The application of what Say pointed out came first in John Finch’s Geological Essay on the Tertiary Formations in America (7, 31, 1824). Even though the paper is still laboring under the mineral system and does not discern the presence of Cretaceous strata among his Tertiary formations, yet Finch also sees that “fossils constitute the medals of the ancient world, by which to ascertain the various periods.”

Finch now objects to the wide misuse in America of the term alluvial and holds that it is applied to what is elsewhere known as Tertiary. He says:

“Geology will achieve a triumph in America, when the term alluvial shall be banished from her Geological Essays, or confined to its legitimate domain, and then her tertiary formations will be seen to coincide with those of Europe, and the formations of London, Paris, and the Isle of Wight, will find kindred associations in Virginia, the Carolinas, Georgias, the Floridas, and Louisiana.”

The formations as he has them from the bottom upwards are: (1) Ferruginous sand, (2) Plastic clay, (3) Calcaire Silicieuse of the Paris Basin, (4) London Clay, (5) Calcaire Ostrée, (6) Upper marine formation, (7) Diluvial.

The grandest of these early stratigraphic papers, however, is that by Lardner Vanuxem (1792–1848), of only three pages, entitled “Remarks on the Characters and Classification of Certain American Rock Formations” (16, 254, 1829). Vanuxem, a cautious man and a profound thinker, had been educated at the Paris School of Mines. James Hall told the writer in a conversation that while the first New York State Survey was in operation, all of its members looked to Vanuxem for advice.

In the paper above referred to, Vanuxem points out in a very concise manner that:

“The alluvial of Mr. Maclure ... contains not only well characterized alluvion, but products of the tertiary and secondary classes. Littoral shells, similar to those of the English and Paris basins, and pelagic shells, similar to those of the chalk deposition or latest secondary, abound in it. These two kinds of shells are not mixed with each other; they occur in different earthy matter, and, in the southern states particularly, are at different levels. The incoherency or earthiness of the mass, and our former ignorance of the true position of the shells, have been the sources of our erroneous views.”

The second error of the older geologists, according to Vanuxem, was the extension of the secondary rocks over “the western country, and the back and upper parts of New York.” They are now called Paleozoic. Some had even tried to show the presence of Jurassic here because of the existence of oölite strata. “It was taken for granted, that all horizontal rocks are secondary, and as the rocks of these parts of the United States are horizontal in their position, so they were supposed to be secondary.” He then shows on the basis of similar Ordovician fossils that the rocks of Trenton Falls, New York, recur at Frankfort in Kentucky, and at Nashville in Tennessee.

“It is also certain that an uplifting or downfalling force, or both, have existed, but it is not certain that either or both these forces have acted in a uniform manner.... Innumerable are the facts, which have fallen under my observation, which show the fallacy of adopting inclination for the character of a class,” such as the Transition class of strata. He then goes on to say that in the interior of our country the so-called secondary rocks are horizontal and in the mountains to the east the same strata are highly inclined. “The analogy, or identity of rocks, I determine by their fossils in the first instance, and their position and mineralogical characters in the second or last instance.”

It appears that Isaac Lea (1792–1886) in his Contributions to Geology, 1833, was the first to transplant to America Lyell’s terms, Pliocene, Miocene, and Eocene, proposed the previous year. The celebrated Claiborne locality was made known to Lea in 1829, and in the work here cited he describes from it 250 species, of which 200 are new. The horizon is correlated with the London Clay and with the Calcaire Grossier of France, both of Eocene time (25, 413, 1834).

Timothy A. Conrad began to write about the American Tertiary in 1830, and his more important publications were issued at Philadelphia. His papers in the Journal begin with 1833 and the last one on the Tertiary is in 1846.

The Tertiary faunas and stratigraphy have been modernized by William H. Dall in his monumental work of 1650 pages and 60 plates entitled “Contributions to the Tertiary Fauna of Florida” (1885–1903). Here more than 3160 forms of the Atlantic and Gulf deposits are described, but in order to understand their relations to the fossil faunas elsewhere and to the living world, the author studied over 10,000 species. Since then, many other workers have interested themselves in the Tertiary problems. Much good work is also being done in the Pacific States where the sequence is being rapidly developed.

The Discerning of the Eastern Cretaceous.—The Cretaceous sequence was first determined by that “active and acute geologist,” Samuel G. Morton (1799–1851), but that these rocks might be present along the Atlantic border had been surmised as early as 1824 by Edward Hitchcock (7, 216). Vanuxem, as above pointed out, indicated the presence of the Cretaceous in 1829. In this same year Morton proved its presence before the Philadelphia Academy of Natural Sciences.

Between 1830 and 1835 Morton published a series of papers in the Journal under the title “Synopsis of the Organic Remains of the Ferruginous Sand Formation of the United States, with Geological Remarks” (17, 274, et seq.). In these he describes the Cretaceous fossils and demonstrates that the “Diluvial” and Tertiary strata of the Atlantic border also have a long sequence of Cretaceous formations. In the opening paper he writes: “I consider the marl of New Jersey as referable to the great ferruginous sand series, which in Prof. Buckland’s arrangement is designated by the name of green sand.... On the continent this series is called the ancient chalk ... lower chalk,” etc. Again, the marls of New Jersey are “geologically equivalent to those beds which in Europe are interposed between the white chalk and the Oölites.” This correlation is with the European Lower Cretaceous, but we now know the marls to be of Upper Cretaceous age. Although Eaton objected strenuously to Morton’s correlation, we find M. Dufresnoy of France saying, “Your limestone above green sand reminds me very much of the Mæstricht beds,” a correlation which stands to this day (22, 94, 1832). In 1833 Morton announces that the Cretaceous is known all along the Atlantic and Gulf border, and in the Mississippi valley. “The same species of fossils are found throughout,” and none of them are known in the Tertiary. He now arranges the strata of the former “Alluvial” as follows:

Modern	Alluvial.
	Diluvial.
Tertiary	Upper Tertiary (Upper Marine).
	Middle Tertiary (London Clay).
	Lower Tertiary (Plastic Clay).
Secondary	Calcareous Strata	Cretaceous group, or Ferruginous Sand series (24, 128).
	Ferruginous Sand

Western Cretaceous.—In 1841 and 1843 J. N. Nicollet announced the discovery of Cretaceous in the Rocky Mountain area. Of 20 species of fossils collected by him, 4 were said to occur on the Atlantic border, and of the 200 forms of the Atlantic slope only 1 was found in Europe. Here we see pointed out a specific dissimilarity between the continents, and a similarity between the American areas of Cretaceous deposits (41, 181; 45, 153).

The Cretaceous of the Rocky Mountains was clearly developed by F. V. Hayden in 1855–1888 and by F. B. Meek (1857–1876). Other workers in this field were Charles A. White (1869–1891), and R. P. Whitfield (1877–1889). Since 1891 T. W. Stanton has been actively interpreting its stratigraphy and faunas.

Cretaceous and Comanche of Texas.—The broader outlines of the Cretaceous of Texas had been described by Ferdinand Roemer in 1852 in his good work, Kreidebildungen von Texas, but it was not until 1887 that Robert T. Hill showed in the Journal (33, 291) that it included two great series, the Gulf series, or what we now call Upper Cretaceous, and a new one, the Comanche series. This was a very important step in the right direction. Since then the Comanche series has been regarded by some stratigraphers as of period value, while others call it Lower Cretaceous; the rest of the Texas Cretaceous is divided by Hill into Middle and Upper Cretaceous. On the other hand, Lower Cretaceous strata had been proved even earlier in the state of California, for here in 1869 W. M. Gabb (1839–1878) and J. D. Whitney (1819–1896) had defined their Shasta group, which was wholly distinct faunally from the Comanche of Texas and the southern part of the Great Plains country.

Jurassic and Triassic of the West.—In 1864, the Geological Survey of California proved the presence of marine Upper Triassic in that State, and since then it has been shown that not only is all of the Triassic present in Idaho (where it has been known since 1877), Oregon, Nevada, and California, but that the Upper Triassic is of very wide distribution throughout western North America. Jurassic strata, on the other hand, were not shown to be present in California until 1885, while in the Rocky Mountain area of the United States there was long known an unresolved series of “Red Beds” situated between the Carboniferous and Cretaceous. This gave rise to the “Red Bed problem,” the history of which is given by C. A. White in the Journal (17, 214, 1879). In 1869, F. V. Hayden announced the discovery of marine Jurassic fossils in this series, and since then they have come to be known as the Sundance fauna, extending from southern Utah and Colorado into Alaska. Above lie the dinosaur-bearing fresh-water deposits, since 1894 known as the Morrison beds. In 1896, O. C. Marsh (1831–1899) announced the presence of Jurassic fresh-water strata along the Atlantic coast (2, 433), but to-day only a small part of them are regarded as of the age of the Morrison, while the far greater part are referred to the Comanche or Lower Cretaceous. The red beds below the Jurassic of the Rocky Mountain area have during the past twenty years been shown to be in part of Upper Triassic age and of fresh-water origin, while the greater lower part is connected with the Carboniferous series and is made up of brackish— and fresh-water deposits of probable Permian time.

Triassic of Atlantic States.—The fresh-water Triassic of the Atlantic border states was first mentioned by Maclure (1817), who regarded it as the equivalent of the Old Red Sandstone of Europe. In this he was followed by Hitchcock in 1823 (6, 39), the latter saying that above it lies “the coal formation,” which is true for Europe, but in America the coal strata are older than these red beds, now known to be of Triassic age.

The first one to question this correlation was Alexandre Brongniart, who had received from Hitchcock rock specimens and a fossil fish which he erroneously identified with a Permian species, and accordingly referred the strata to the Permian (3, 220, 1821; 6, 76, pl. 9, figs. 1, 2, 1823). The discerning Professor Finch in 1826 remarked that the red beds of Connecticut appear to belong “to the new or variegated sandstone,” because of eight different criteria that he mentions. Of these, but two are of value in correlation, their “geological position” and the presence of bones other than fishes. In the Connecticut area, however, the geological position cannot be determined even to-day, and in Finch’s time the bones of dinosaurs were unknown. Finch then goes on to point out the occurrences of Old Red Sandstone in Pennsylvania, but all of the places he refers to are either younger or older in time. Here we again see the fatality of trying to make positive correlations on the basis of lithology and color (10, 209, 1826). In 1835, however, Hitchcock showed that the bones that had been found in 1820 were those of a saurian, and accordingly referred the strata of the Connecticut valley to the New Red Sandstone, a term that then covered both the Permian and the Triassic. In 1842, W. B. Rogers referred the beds to the Jurassic, on the basis of plants from Virginia. In 1856, W. C. Redfield (1789–1857), because of the fishes, advocated a Lias, or Jurassic age, and proposed the name Newark group for all the Triassic deposits of the Atlantic border. More recently, on the basis of the plants studied by Newberry, Fontaine, Sturr, and Ward, and the vertebrates described by Marsh and Lull, the age has been definitely fixed as Upper Triassic (see Dana’s Manual of Geology, 740, 1895).

Unearthing of the Paleozoic in North America.

Permian of the United States.—In Europe, previous to 1841, the formations now classed as Permian were included in the New Red Sandstone, and with the Carboniferous were referred to the Secondary. In that year Murchison proposed the period term Permian. In 1845 came the classic Geology of Russia in Europe and the Ural Mountains, by Murchison, Keyserling, and De Verneuil. In this great work the authors separated out of the New Red the Magnesian Limestone of Great Britain and the Rothliegende marls, Kupferschiefer, and Zechstein of Germany, and with other formations of the Urals in Russia, referred them to the Permian system. This step, one of the most discerning in historical geology, was all the more important because they closed the Paleozoic era with the Permian, beginning the Secondary, or Mesozoic, with the New Red Sandstone or the Triassic period. There is a good review of this work by D. D. Owen (1807–1860) in the Journal for 1847 (3, 153).

Owen, though accepting the Permian system, is not satisfied with its reference to the Paleozoic, and he sets the matter forth in the Journal (3, 365, 1847). He doubts “the propriety of a classification which throws the Permian and Carboniferous systems into the Paleozoic period.” This is mainly because there is no “evidence of disturbance or unconformability” between the Permian and Triassic systems. Rather “there is so complete a blending of adjacent strata” that it is only in Russia that the Permian has been distinguished from the Triassic. This view of Owen’s was not only correct for Russia but even more so for the Alps and for India, and it has taken a great deal of work and discussion to fix upon the disconformable contact that distinguishes the Paleozoic from the Mesozoic in these areas. In other words, there was here at this time no mountain making. Then Owen goes on to state that because the Permian of Europe has reptiles, he sees in them decisive Mesozoic evidence. “These are certainly strong arguments in favor of placing, not only the Permian, but also the Carboniferous group in the Mesozoic period, and terminating the Paleozoic division with the commencement of the coal measures.” To this harking backward the geologists of the world have not agreed, but have followed the better views of Murchison and his associates.

In 1855 G. G. Shumard discovered, and in 1860 his brother B. F. Shumard (1820–1869) announced, the presence of Permian strata in the Guadalupe Mountains of Texas, and in 1902 George H. Girty (14, 363) confirmed this. Girty regards the faunas as younger than any other late Paleozoic ones of America, and says: “For this reason I propose to give them a regional name, which shall be employed in a force similar to Mississippian and Pennsylvanian.... The term Guadalupian is suggested.”

G. C. Swallow (1817–1899) in 1858 was the first to announce the presence of Permian fossils in Kansas, and this led to a controversy between himself and F. B. Meek, both claiming the discovery. It is only in more recent years that it has been generally admitted that there is Permian in that state, in Oklahoma, and in Texas. This admission came the more readily through the discovery of many reptiles in the red beds of Texas, and through the work of C. A. White, published in 1891, The Texan Permian and its Mesozoic Types of Fossils (Bull. U. S. Geological Survey, No. 77).

Carboniferous Formations.—The coal formations are noted in a general way throughout the earliest volumes of the Journal. The first accounts of the presence of coal, in Ohio, are by Caleb Atwater (1, 227, 239, 1819), and S. P. Hildreth (13, 38, 40, 1828). The first coal plants to be described and illustrated were also from Ohio, in an article by Ebenezer Granger in 1821 (3, 5–7). The anthracite field was first described in 1822 by Zachariah Cist (4, 1) and then by Benjamin Silliman (10, 331–351, 1826); that of western Pennsylvania was described by William Meade in 1828 (13, 32).

The Lower Carboniferous was first recognized by W. W. Mather in 1838 (34, 356). Later, through the work of Alexander Winchell (1824–1891), beginning in 1862 (33, 352) and continuing until 1871, and through the surveys of Iowa (1855–1858), Illinois (essentially the work of A. H. Worthen, 1858–1888), Ohio (1838, Mather, etc.), and Indiana (Owen, etc., 1838), there was eventually worked out the following succession:

Permian period.

Upper Barren series.

Dunkard group.

Washington group.

Pennsylvanian period.

Upper Productive Coal series. Monongahela series.

Lower Barren Coal Measures. Conemaugh series.

Lower Productive Coal Measures. Allegheny series.

Pottsville series.

The New York System.—We now come to the epochal survey of the State of New York, one that established the principles of, and put order into, American stratigraphy from the Upper Cambrian to the top of the Devonian. No better area could have been selected for the establishing of this sequence. This survey also developed a stratigraphic nomenclature based on New York localities and rock exposures, and made full use of the entombed fossils in correlation. Incidentally it developed and brought into prominence James Hall, who continued the stratigraphic work so well begun and who also laid the foundation for paleontology in America, becoming its leading invertebrate worker.

This work is reviewed at great length in the Journal in the volumes for 1844–1847 by D. D. Owen. Evidently it followed too new a plan to receive fulsome praise from conservative Owen, as it should have. He remarks that the volumes “are not a little prolix, are voluminous and expensive, and do not give as clear and connected a view of the geological features of the state as could be wished.... We are of the opinion that before this work can become generally useful and extensively circulated, it must be condensed and arranged into one compendious volume” (46, 144, 1844). This was never done and yet the work was everywhere accepted at once, and to this end undoubtedly Owen’s detailed review helped much.

The Natural History Survey of New York was organized in 1836 and completed in 1843. The state was divided into four districts, and to these were finally assigned the following experienced geologists. The southeastern part was named the First District, with W. W. Mather (1804–1859) as geologist; the northeastern quarter was the Second District, with Ebenezer Emmons (1799–1863) in charge; the central portion was the Third District, under Lardner Vanuxem (1792–1848); while the western part was James Hall’s (1811–1898) Fourth District. Paleontology for a time was in charge of T. A. Conrad (1830–1877); the mineralogical and chemical work was in the hands of Lewis C. Beck; the botanist was John Torrey; and the zoologist James DeKay.

The New York State Survey published six annual reports of 1675 pages octavo, and four final geological reports with 2079 pages quarto. Finally in 1846 Emmons added another volume on the soils and rocks of the state, in which he also discussed the Taconic and New York systems; it has 371 pages. With the completion of the first survey, Hall took up his life work under the auspices of the state—his monumental work, Paleontology of New York, in fifteen quarto volumes of 4539 pages and 1081 plates of fossils. In addition to all this, there are his annual and other reports to the Regents of the State, so that it is safe to say that he published not less than 10,000 pages of printed matter on the geology and paleontology of North America.

In regard to this great series of works, all that can be presented here is a table of formations as developed by the New York State Survey. Practically all of its results and formation names have come into general use, with the exception of the Taconic system of Emmons and the division terms of the New York system. (See p. 88.)

The New York State Survey, begun in 1836, was continued by James Hall from 1843 to 1898. During this time he was also state geologist of Iowa (1855–1858) and Michigan (1862). Since 1898, John M. Clarke has ably continued the Geological Survey of New York, the state which continues to be, in science and more especially in geology and paleontology, the foremost in America.

Western Extension of the New York system.—Before Hall finished his final report, we find him in 1841 on “a tour of exploration through the states of Ohio, Indiana, Illinois, a part of Michigan, Kentucky, and Missouri, and the territories of Iowa and Wisconsin.” This tour is described in the Journal (42, 51, 1842) under the caption “Notes upon the Geology of the Western States.” His object was to ascertain how far the New York system as the standard of reference “was applicable in the western extension of the series.” In a general way he was very successful in extending the system to the Mississippi River, and he clearly saw “a great diminution, first of sandy matter, and next of shale, as we go westward, and in the whole, a great increase of calcareous matter in the same direction.” He also clearly noted the warped nature of the strata, the “anticlinal axis,” since known as the Cincinnati and Wabash uplifts and the Ozark dome.

Hall, however, fell into a number of flagrant errors because of a too great reliance on lithologic correlation and supposedly similar sequence. For instance, the Coal Measures of Pennsylvania were said to directly overlap the Chemung group of southern New York, and now he finds the same condition in Ohio, Indiana, and Illinois, failing to see that in most places between the top of the New York system and the Coal Measures lay the extensive Mississippian series, one that he generally confounded with the Chemung, or included in the “Carboniferous group.” He states that the Portage of New York is the same as the Waverly of Ohio, and at Louisville the Middle Devonian waterlime is correlated with the similar rock of the New York Silurian. Hall was especially desirous of fixing the horizon of the Middle Ordovician lead-bearing rocks of Illinois, Wisconsin, and Iowa, but unfortunately correlated them with the Niagaran, while the Middle Devonian about Columbus, Ohio, and Louisville, Kentucky, he referred to the same horizon. The Galena-Niagaran error was corrected in 1855, but the Devonian and Mississippian ones remained unadjusted for a long time, and in Iowa until toward the close of the nineteenth century.

The Geological Column of the New York Geologists of 1842–1843, according to W. W. Mather 1842.
Quaternary system	Alluvial division.
	Quaternary division.
	Drift division.
Tertiary system	These strata are included in the next lower division.
Upper Secondary system	Long Island division. Equals the Tertiary and Cretaceous marls, sands, and clays of the coastal plain of New Jersey.	New Red system of Emmons and Hall.
	Trappean division. The Palisades
	Red Sandstone division.

Coal system of Mather, and Carboniferous system of Hall.

Old Red system of Catskill Mountains of Emmons; Catskill division of Mather and Hall; and Catskill group of Vanuxem.

According to Hall 1843, and essentially Vanuxem 1842.
Erie division [Devonian]	Chemung, Portage or Nunda (divided into Cashaqua, Gardeau, Portage), Genesee, Tully, Hamilton (divided into Ludlowville; Encrinal, Moscow), and Marcellus.
Helderberg series [Devonian-Silurian]	Corniferous, Onondaga, Schoharie, Cauda-alli, Oriskany, Upper Pentamerus, Encrinal, Delthyris, Pentamerus, Waterlime, Onondaga salt group.
Ontario division [Silurian]	Niagara, Clinton, and Medina.
Champlain division [Silurian-Ordovician-Upper Cambrian]	Oneida or Shawangunk, Grey sandstone, Hudson River group, Utica, Trenton, Black River including Birdseye and Chazy, Calciferous sandrock, and Potsdam.

According to Emmons 1842, Mather 1843, Vanuxem 1842, Hall 1843.
Taconic System [Ordovician and Lower Cambrian]	Granular quartz, Stockbridge limestone, Magnesian slate, and Taconic slate.
Primary or Hypogene system	Metamorphic and Primary rocks.

Correlations with Europe.—The first effort toward correlating the New York system with those of Europe was made by Conrad in his Notes on American Geology in 1839 (35, 243). Here he compares it on faunal grounds with the Silurian system. A more sustained effort was that of Hall in 1843 (45, 157), when he said that the Silurian of Murchison was equal to the New York system and embraced the Cambrian, Silurian, and Devonian, which he considered as forming but one system. Hall in 1844 and Conrad earlier were erroneously regarding the Middle Devonian of New York (Hamilton) as “an equivalent of the Ludlow rocks of Mr. Murchison” (47, 118, 1844).

In 1846 E. P. De Verneuil spent the summer in America with a view to correlating the formations of the New York system with those of Europe. At this time he had had a wide field experience in France, Germany, and Russia, was president of the Geological Society of France, and “virtually the representative of European geology” (2, 153, 1846). Hall says, “No other person could have presented so clear and perfect a coup d’oeil.” De Verneuil’s results were translated by Hall and with his own comments were published in the Journal in 1848 and 1849 under the title “On the Parallelism of the Paleozoic Deposits of North America with those of Europe.” De Verneuil was especially struck with the complete development of American Paleozoic deposits and said it was the best anywhere. On the other hand, he did not agree with the detailed arrangement of the formations in the various divisions of the New York system, and Hall admitted altogether too readily that the terms were proposed “as a matter of concession, and it is to be regretted that such an artificial classification was adopted.” De Verneuil’s correlations are as follows:

The Lower Silurian system begins with the Potsdam, the analogue of the Obolus sandstone of Russia and Sweden. The Black River and Trenton hold the position of the Orthoceras limestones of Sweden and Russia, while the Utica and Lorraine are represented by the Graptolite beds of the same countries. Both correlations are in partial error. He unites the Chazy, Birdseye, and Black River in one series, and in another the Trenton, Utica, and Lorraine. Of species common to Europe and America he makes out seventeen.

In the Upper Silurian system, the Oneida and Shawangunk are taken out of the Champlain division, and, with the Medina, are referred to the Silurian, along with all of the Ontario division plus the Lower Helderberg. The Clinton is regarded as highest Caradoc or as holding a stage between that and the Wenlock. The Niagara group is held to be the exact equivalent of the Wenlock, “while the five inferior groups of the Helderberg division represent the rocks of Ludlow.” We now know that these Helderberg formations are Lower Devonian in age. De Verneuil unites in one series the Waterlime, Pentamerus, Delthyris, Encrinal, and Upper Pentamerus. Of identical species there are forty common to Europe and America.

The Devonian system De Verneuil begins, “after much hesitation,” with the Oriskany and certainly with the five upper members of Hall’s Helderberg division, all of the Erie and the Old Red Sandstone. He also adjusts Hall’s error by placing in the Devonian the Upper Cliff limestone of Ohio and Indiana, regarded by the former as Silurian. The Oriskany is correlated with the grauwackes of the Rhine, and the Onondaga or Corniferous with the lower Eifelian. Cauda-galli, Schoharie, and Onondaga are united in one series; Marcellus, Hamilton, Tully, and Genesee in another; and Portage and Chemung in a third. Of species common to Europe and America there are thirty-nine.

The Waverly of Ohio and that near Louisville, Kentucky, which Hall had called Chemung, De Verneuil correctly refers to the Carboniferous, but to this Hall does not consent. De Verneuil points out that there are thirty-one species in common between Europe and America. “And as to plants, the immense quantity of terrestrial species identical on the two sides of the Atlantic, proves that the coal was formed in the neighborhood of lands already emerged, and placed in similar physical conditions.”

An analysis of the Paleozoic fossils of Europe and America leads De Verneuil to “the conviction that identical species have lived at the same epoch in America and in Europe, that they have had nearly the same duration, and that they succeeded each other in the same order.” This he states is independent of the depth of the seas, and of “the upheavings which have affected the surface of the globe.” The species of a period begin and drop out at different levels, and toward the top of a system the whole takes on the character of the next one. “If it happens that in the two countries a certain number of systems, characterized by the same fossils, are superimposed in the same order, whatever may be, otherwise, their thickness and the number of physical groups of which they are composed, it is philosophical to consider these systems as parallel and synchronous.”

Because of the dominance of the sandstones and shales in eastern New York, De Verneuil holds that a land lay to the east. The many fucoids and ripple-marks from the Potsdam to the Portage indicated to him shallow water and nearness to a shore.

The Oldest Geologic Eras.—We have seen in previous pages how the Primitive rocks of Arduino and of Werner had been resolved, at least in part, into the systems of the Paleozoic, but there still remained many areas of ancient rocks that could not be adjusted into the accepted scheme. One of the most extensive of these is in Canada, where the really Primitive formations, of granites, gneisses, schists, and even undetermined sediments, abound and are developed on a grander scale than elsewhere, covering more than two million square miles and overlain unconformably by the Paleozoic and later rocks. The first to call attention to them was J. I. Bigsby, a medical staff officer of the British Army, in 1821 (3, 254). It was, however, William E. Logan (1798–1875), the “father of Canadian geology,” who first unravelled their historical sequence. At first he also called them Primary, but after much work he perceived in them parallel structures and metamorphosed sediments, underlain by and associated with pink granites. For the oldest masses, essentially the granites, he proposed the term Laurentian system (1853, 1863) and for the altered and deformed strata, the name Huronian series (1857, 1863). Overlying these unconformably was a third series, the copper-bearing rocks. Since his day a great host of Canadian and American geologists have labored over this, the most intricate of all geology, and now we have the following tentative chronology (Schuchert and Barrell, 38, 1, 1914):

Late Proterozoic era.

Keweenawan, Animikian and Huronian periods.

Early Proterozoic era.

Sudburian period or older Huronian.

Archeozoic era.

Grenville series, etc.

Cosmic history.

The Taconic System Resurrected.

The Taconic system was first announced by Ebenezer Emmons in 1841, and clearly defined in 1842. It started the most bitter and most protracted discussion in the annals of American geology. After Emmons’s subsequent publications had put the Taconic system through three phases, Barrande of Bohemia in 1860–1863 shed a great deal of new and correct light upon it, affirming in a series of letters to Billings that the Taconic fossils are like those of his Primordial system, or what we now call the Middle Cambrian (31, 210, 1861, et seq.).

In a series of articles published by S. W. Ford in the Journal between 1871 and 1886, there was developed the further new fact that in Rensselaer and Columbia counties, New York, the so-called Hudson River group abounds in “Primordial” fossils wholly unlike those of the Potsdam, and which Ford later on spoke of as belonging to “Lower Potsdam” time.

James D. Dana entered the field of the Taconic area in 1871 and demonstrated that the system also abounds in Ordovician fossiliferous formations. Then came the far-reaching work of Charles D. Walcott, beginning in 1886, which showed that all through eastern New York and into northern Vermont the Hudson River group and the Taconic system abound not only in Ordovician but also in Cambrian fossils. Finally in 1888 Dana presented a Brief History of Taconic Ideas, and laid away the system with these words (36, 27):

“It is almost fifty years since the Taconic system made its abrupt entrance into geological science. Notwithstanding some good points, it has been through its greater errors, long a hindrance to progress here and abroad ... But, whether the evil or the good has predominated, we may now hope, while heartily honoring Professor Emmons for his earnest geological labors and his discoveries, that Taconic ideas may be allowed to be and remain part of the past.”

As an epitaph Dana placed over the remains of the Taconic system the black-faced numerals 1841–1888. That the remains of the system, however, and the term Taconic are still alive and demanding a rehearing is apparent to all interested stratigraphers. This is not the place to set the matter right, and all that can be done at the present time is to point out what are the things that still keep alive Emmons’s system.

In the typical area of the Taconic system, i. e., in Rensselaer County, Emmons in 1844–1846 produced the fossils Atops trilineatus and Elliptocephala asaphoides. S. W. Ford, as stated above, later produced from the same general area many other fossils that he demonstrated to be older than the Potsdam sandstone. To this time he gave the name of Lower Potsdam, thus proving on paleontological grounds that at least some part of the Taconic system is older than the New York system, and therefore older than the Hudson River group of Ordovician age.

In 1888 Walcott presented his conclusions in regard to the sequence of the strata in the typical Taconic area and to the north and south of it. He collected Lower Cambrian fossils at more than one hundred localities “within the typical Taconic area,” and said that the thickness of his “terrane No. 5” or “Cambrian (Georgia),” now referable to the Lower Cambrian, is “14,000 feet or more.” He demonstrated that the Lower Cambrian is infolded with the Lower and Middle Ordovician, and confirmed Emmons’s statement that the former rests upon his Primary or Pre-Cambrian masses. Elsewhere, he writes: “To the west of the Taconic range the section passes down through the limestone (3) [of Lower and Middle Ordovician age] to the hydromica schists (2) [whose age may also be of early Ordovician], and thence to the great development of slates and shales with their interbedded sparry limestones, calciferous and arenaceous strata, all of which contain more or less of the Olenellus ... fauna.” He then knew thirty-five species in Washington County, New York (35, 401, 1888).

Finally in 1915 Walcott said that in the Cordilleran area of America there was a movement that brought about changes “in the sedimentation and succession of the faunas which serve to draw a boundary line between the Lower and Middle Cambrian series.... The length of this period of interruption must have been considerable ... and when connection with the Pacific was resumed a new fauna that had been developing in the Pacific was then introduced into the Cordilleran sea and constituted the Middle Cambrian fauna. The change in the species from the Lower to the Middle Cambrian fauna is very great.” He then goes on to show that in the Appalachian geosyncline there was another movement that shut out the Middle Cambrian Paradoxides fauna of the Atlantic realm from this trough, and all deposition as well.

Conclusions.—Accordingly it appears that everywhere in America the Lower Cambrian formations are separated by a land interval of long duration from those of Middle Cambrian time. These formations therefore unite into a natural system of rocks or a period of time. Between Middle and Upper Cambrian time, however, there appears to be a complete transition in the Cordilleran trough, binding these two series of deposits into one natural or diastrophic system. Hence the writer proposes that the Lower Cambrian of America be known as the Taconic system. The Middle and Upper Cambrian series can be continued for the present under the term Cambrian system, a term, however, that is by no means in good standing for these formations, as will be demonstrated under the discussion of the Silurian controversy.

The Silurian Controversy.

Just as in America the base of the Paleozoic was involved in a protracted controversy, so in England the Cambrian-Silurian succession was a subject of long debate between Sedgwick and Murchison, and among the succeeding geologists of Europe. The history of the solution is so well and justly stated in the Journal by James D. Dana under the title “Sedgwick and Murchison: Cambrian and Silurian” (39, 167, 1890), and by Sir Archibald Geikie in his Text-book of Geology, 1903, that all that is here required is to briefly restate it and to bring the solution up to date.

Adam Sedgwick (1785–1873) and R. I. Murchison (1792–1871) each began to work in the areas of Cambria (Wales) and Siluria (England) in 1831, but the terms Cambrian and Silurian were not published until 1835. Murchison was the first to satisfactorily work out the sequence of the Silurian system because of the simpler structural and more fossiliferous condition of his area. Sedgwick, on the other hand, had his academic duties to perform at Cambridge University, and being an older and more conservative man, delayed publishing his final results, because of the further fact that his area was far more deformed and less fossiliferous. In 1834 they were working in concert in the Silurian area, and Sedgwick said: “I was so struck by the clearness of the natural sections and the perfection of his workmanship that I received, I might say, with implicit faith everything which he then taught me.... The whole ‘Silurian system’ was by its author placed above the great undulating slate-rocks of South Wales.” At that time Murchison told Sedgwick that the Bala group of the latter, now known to be in the middle of the Lower Silurian, could not be brought within the limits of the Silurian system, and added, “I believe it to plunge under the true Llandeilo-flags,” now placed next below the Bala and above the Arenig, which at the present is regarded as at the base of the Ordovician.

The Silurian system was defined in print by Murchison in July, 1835, the Upper Silurian embracing the Ludlow and Wenlock, while the Lower Silurian was based on the Caradoc and Llandeilo. Murchison’s monumental work, The Silurian System, of 100 pages and many plates of fossils, appeared in 1838.

The Cambrian system was described for the first time by Sedgwick in August, 1835, but the completed work—a classic in geology—Synopsis of the Classification of the British Palæozoic Rocks, along with M’Coy’s Descriptions of British Palæozoic Fossils, did not appear until 1852–1855. Sedgwick’s original Upper Cambrian included the greater part of the chain of the Berwyns, where he said it was connected with the Llandeilo flags of the Silurian. The Middle Cambrian comprised the higher mountains of Cærnarvonshire and Merionethshire, and the Lower Cambrian was said to occupy the southwest coast of Cærnarvonshire, and to consist of chlorite and mica schists, and some serpentine and granular limestone. In 1853 it was seen that the fossiliferous Upper Cambrian included the Arenig, Llandeilo, Bala, Caradoc, Coniston, Hirnant, and Lower Llandovery. On the other hand, it was not until long after Murchison and Sedgwick passed away that the Middle and Lower Cambrian were shown to have fossils, but few of those that characterize what is now called Lower, Middle, and Upper Cambrian time.

Not until long after the original announcement of the Cambrian system did Sedgwick become aware “of the unfortunate mischief-involving fact” that the most fossiliferous portion of the Cambrian—the Upper Cambrian—and at that time the only part yielding determinable fossils, when compared with the Lower Silurian was seen to be an equivalent formation but with very different lithologic conditions. He began to see in 1842 that his Cambrian was in conflict with the Silurian system, and four years later there were serious divergencies of views between himself and Murchison. The climax of the controversy was attained in 1852, when Sedgwick was extending his Cambrian system upwards to include the Bala, Llandeilo, and Caradoc, a proceeding not unlike that of Murchison, who earlier had been extending his Silurian downward through all of the fossiliferous Cambrian to the base of the Lingula flags.

Dana in his review of the Silurian-Cambrian controversy states: “The claim of a worker to affix a name to a series of rocks first studied and defined by him cannot be disputed.” We have seen that Murchison had priority of publication in his term Silurian over Sedgwick’s Cambrian, but that in a complete presentation, both stratigraphically and faunally, the former had years of prior definition. What has even more weight is that geologists nearly everywhere had accepted Murchison’s Silurian system as founded upon the Lower and Upper Silurian formations. A nomenclature once widely accepted is almost impossible to dislodge. However, in regard to the controversy it should not be forgotten that it was only Murchison’s Lower Silurian that was in conflict with Sedgwick’s Upper Cambrian. As for the rest of the Cambrian, that was not involved in the controversy.

Dana goes on to state that science may accept a name, or not, according as it is, or is not, needed. In the progress of geology, he thought that the time had finally been reached when the name Cambrian was a necessity, and he included both Cambrian and Silurian in the geological record. The “Silurian,” however, included the Lower and Upper Silurian—not one system of rocks, but two.

It is now twenty-seven years since Dana came to this conclusion, at a time when it was believed that there was more or less continuous deposition not only between the formations of a system but between the systems themselves as well. To-day many geologists hold that in the course of time the oceans pulsate back and forth over the continents, and accordingly that the sequence of marine sedimentation in most places must be much broken, and to-day we know that the breaks or land intervals in the marine record are most marked between the eras, and shorter between all or at least most of the periods. Furthermore, in North America, we have learned that the breaks between the systems are most marked in the interior of the continent and less so on or toward its margins.

Hardly any one now questions the fact of a long land interval between the Lower Silurian and Upper Silurian in England, and it is to Sedgwick’s credit that he was the first to point out this fact and also the presence of an unconformity. It therefore follows that we cannot continue to use Silurian system in the sense proposed by Murchison, since it includes two distinct systems or periods. Dana, in the last edition of his Manual of Geology (1895), also recognizes two systems, but curiously he saw nothing incongruous in calling them “Lower Silurian era” and “Upper Silurian era.” It certainly is not conducive to clear thinking, however, to refer to two systems by the one name of Silurian and to speak of them individually as Lower and Upper Silurian, thus giving the impression that the two systems are but parts of one—the Silurian. Each one of the parts has its independent faunal and physical characters.

We must digress a little here and note the work of Joachim Barrande (1799–1883) in Bohemia. In 1846 he published a short account of the “Silurian system” of Bohemia, dividing it into étages lettered C to H. Between 1852 and 1883 he issued his “Système Silurien du Centre de la Bohème,” in eighteen quarto volumes with 5568 pages of text and 798 plates of fossils—a monumental work unrivalled in paleontology. In the first volume the geology of Bohemia is set forth, and here we see that étages A and B are Azoic or pre-Cambrian, and C to H make up his Silurian system. Etage C has his “Primordial fauna,” now known to be of Paradoxides or Middle Cambrian time, while D is Lower Silurian, E is Upper Silurian, F is Lower Devonian, and G and H are Middle Devonian. From this it appears that Barrande’s Silurian system is far more extensive than that of Murchison, embracing twice as many periods as that of England and Wales.

About 1879 there was in England a nearly general agreement that Cambrian should embrace Barrande’s Primordial or Paradoxides faunas, and in the North Wales area be continued up to the top of the Tremadoc slates. To-day we would include Middle and Upper Cambrian. Lower Cambrian in the sense of containing the Olenellus faunas was then unknown in Great Britain.

Lapworth, recognizing the distinctness of the Lower Silurian as a system, proposed in 1879 to recognize it as such, and named it Ordovician, restricting Silurian to Murchison’s Upper Silurian. This term has not been widely used either in Great Britain or on the Continent, but in the last twenty years has been accepted more and more widely in America. Even here, however, it is in direct conflict with the term Champlain, proposed by the New York State Geologist in 1842.

In 1897 the International Geological Congress published E. Renevier’s Chronographie Géologique, wherein we find the following:

Silurian Period.	Upper or Silurian (Murchison, restricted, 1835).	Ludlowian (Murchison 1839).
		Wenlockian (Murchison 1839).
		Landoverian (Murchison).
	Middle or Ordovician (Lapworth 1879).	Caradocian (Murchison 1839).
		Landeilian (Murchison 1839).
		Arenigian (Sedgwick 1847).
	Lower or Cambrian (Sedgwick, restricted, 1835).	Potsdamian (Emmons 1838).
		Menevian (Salter and Hicks 1865).
		Georgian (Hitchcock 1861).

Regarding this period, which, by the way, is not very unlike that of Barrande, Renevier remarks that it is “as important as the Cretaceous or the Jurassic. Lapworth even gives it a value of the first order equal to the Protozoic era.”

In the above there is an obvious objection in the double usage of the term Silurian, and this difficulty was met later on in Lapparent’s Traité by the proposal to substitute Gothlandian for Silurian. Of this change Geikie remarks: “Such an arrangement ... might be adopted if it did not involve so serious an alteration of the nomenclature in general use.” On the other hand, if diastrophism and breaks in the stratigraphic and faunal sequence are to be the basis for geologic time divisions, we cannot accept the above scheme, for it recognizes but one period where there are at least four in nature.

Conclusions.—We have arrived at a time when our knowledge of the stratigraphic and faunal sequence, plus the orogenic record as recognized in the principle of diastrophism, should be reflected in the terminology of the geologic time-table. It would be easy to offer a satisfactory nomenclature if we were not bound by the law of priority in publication, and if no one had the geologic chronology of his own time ingrained in his memory. In addition, the endless literature, with its accepted nomenclature, bars our way. Therefore with a view of creating the least change in geologic nomenclature, and of doing the greatest justice to our predecessors that the present conditions of our knowledge will allow, the following scheme is offered:

Silurian period. Llandovery to top of Ludlow in Europe. Alexandrian-Cataract-Medina to top of Manlius in America.

Champlain (1842) or Ordovician (1879) period. Arenig to top of Caradoc in Europe. Beekmantown to top of Richmondian in America.

Cambrian period. In the Atlantic realm, begins with the Paradoxides, and in the Pacific, with the Bathyuriscus and Ogygopsis faunas. The close is involved in Ulrich’s provisionally defined Ozarkian system. When the latter is established, the Ozarkian period will hold the time between the Ordovician and the Cambrian.

Taconic period. For the world-wide Olenellus or Mesonacidæ faunas.

Paleogeography.

When geologists began to perceive the vast significance of Hutton’s doctrine that “the ruins of an earlier world lie beneath the secondary strata,” and that great masses of bedded rocks are separated from one another by periods of mountain making and by erosion intervals, it was natural for them to look for the lands that had furnished the debris of the accumulated sediments. In this way paleogeography had its origin, but it was at first of a descriptive and not of a cartographic nature.

The word paleogeography was proposed by T. Sterry Hunt in 1872 in a paper entitled “The Paleogeography of the North American Continent,” and published in the Journal of the American Geographical Society for that year. It has to do, he says, with the “geographical history of these ancient geological periods.” It was again prominently used by Robert Etheridge in his presidential address before the Geological Society of London in 1881. Since Canu’s use of the term in 1896, it has been frequently seen in print, and now is generally adopted to signify the geography of geologic time.

The French were the first to make paleogeographic maps, and Jules Marcou relates in 1866 that Elie de Beaumont, as early as March, 1831, in his course in the College of France and at the Paris School of Mines, used to outline the relation of the lands and the seas in the center of Europe at the different great geologic periods. His first printed paleogeographic map appeared in 1833, and was of early Tertiary time. Other maps by Beaumont were published by Beudant in 1841–1842. The Sicilian geologist Gemmellaro published six maps of his country in 1834, and the Englishman De La Beche had one in the same year. In America the first to show such maps was Arnold Guyot in his Lowell lectures of 1848. James D. Dana published three in the 1863 edition of his Manual of Geology. Of world paleogeographic maps, Jules Marcou produced the first of Jurassic time, publishing it in France in 1866, but the most celebrated of these early attempts was the one by Neumayr published in 1883 in connection with his Ueber klimatische Zonen während der Jura- und Kreidezeit.

The first geologist to produce a series of maps showing the progressive geologic geography of a given area was Jukes-Brown, who in the volume entitled “The Building of the British Isles,” 1888, included fifteen such maps. Karpinsky published fourteen maps of Russia, and in 1896 Canu in his Essai de paléogéographie has fifty-seven of France and Belgium. Lapparent’s Traité of 1906 is famous for paleogeographic maps, for he has twenty-three of the world, thirty-four of Europe, twenty-five of France, and ten taken from other authors. Schuchert in 1910 published fifty-two to illustrate the paleogeography of North America, and also gave an extended list of such published maps. Another article on the subject is by Th. Arldt, “Zur Geschichte der Paläogeographischen Rekonstructionen,” published in 1914. Edgar Dacqué in 1913 also produced a list in his Paläogeographischen Karten, and two years later appeared his book of 500 pages, Grundlagen und Methoden der Paläogeographie, where the entire subject is taken up in detail.

Conclusions.—Since 1833 there have been published not less than 500 different paleogeographic maps, and of this number about 210 relate to North America. Nevertheless paleogeography is still in its infancy, and most maps embrace too much geologic time, all of them tens of thousands, and some of them millions of years. The geographic maps of the present show the conditions of the strand-lines of to-day, and those made fifty years ago have to be revised again and again if they are to be of value to the mariner and merchant. Therefore in our future paleogeographic maps the tendency must ever be toward smaller amounts of geologic time, if we are to show the actual relation of water to land and the movements of the periodic floodings. Moreover, the ancient shore lines are all more or less hypothetic and are drawn in straight or sweeping curves, unlike modern strands with their bays, deltas, and headlands, and the ancient lands are featureless plains. We must also pay more attention to the distribution of brackish- and fresh-water deposits. The periodically rising mountains will be the first topographic features to be shown upon the ancient lands, and then more and more of the drainage and the general climatic conditions must be portrayed. In the seas, depth, temperature, and currents are yet to be deciphered. Finally, other base maps than those of the geography of to-day will have to be made, allowing for the compression of the mountainous areas, if we are to show the true geographic configurations of the lands and seas of any given geologic time.

Paleometeorology.

In accordance with the Laplacian theory, announced at the beginning of the nineteenth century, all of the older geologists held that the earth began as a hot star, and that in the course of time it slowly cooled and finally attained its present zonal cold to tropical climatic conditions. That the earth had very recently passed through a much colder climate, a glacial one, came into general acceptance only during the latter half of the previous century.

Rise.—Our knowledge of glacial climates had its origin in the Alps, that wonderland of mountains and glaciers. The rise of this knowledge in the Alps is told in a charming and detailed manner by that erratic French-American geologist, Jules Marcou (1824–1898), in his Life, Letters, and Works of Louis Agassiz, 1896. He relates that the Alpine chamois hunter Perraudin in 1815 directed the attention of the engineer De Charpentier to the fact “that the large boulders perched on the sides of the Alpine valleys were carried and left there by glaciers.” For a long time the latter thought the conclusion extravagant, and in the meantime Perraudin told the same thing to another engineer, Venetz. He, in 1829, convinced of the correctness of the chamois hunter’s views, presented the matter before the Swiss naturalists then meeting at St. Bernard’s. Venetz “told the Society that his observations led him to believe that the whole Valais has been formerly covered by an immense glacier and that it even extended outside of the canton, covering all the Canton de Vaud, as far as the Jura Mountains, carrying the boulders and erratic materials, which are now scattered all over the large Swiss valley.” Eight years earlier, in 1821, similar views had been presented by the same modest naturalist before the Helvetic Society, but it was not until 1833 that De Charpentier found the manuscript and had it published. Venetz’s conclusions were that all of the glaciers of the Bagnes valley “have very recognizable moraines, which are about a league from the present ice.” “The moraines ... date from an epoch which is lost in the night of time.” Then in 1834 De Charpentier read a paper before the same society, meeting at Lucerne. “Seldom, if ever, has such a small memoir so deeply excited the scientific world. It was received at first with incredulity and even scorn and mockery, Agassiz being among its opponents.” The paper was published in 1835, first at Paris, then at Geneva, and finally in Germany. It “attracted much attention, and the smile of incredulity with which it was received when read at Lucerne soon changed into a desire to know more about it.”

Louis Agassiz (1807–1873), who had long been acquainted with his countryman, De Charpentier, spent several months with him in 1836, and together they studied the glaciers of the Alps. Agassiz was at first “adverse to the hypothesis, and did not believe in the great extension of glaciers and their transportation of boulders, but on the contrary, was a partisan of Lyell’s theory of transport by icebergs and ice-cakes ... but from being an adversary of the glacial theory, he returned to Neuchâtel an enthusiastic convert to the views of Venetz and De Charpentier.... With his power of quick perception, his unmatched memory, his perspicacity and acuteness, his way of classifying, judging and marshalling facts, Agassiz promptly learned the whole mass of irresistible arguments collected patiently during seven years by De Charpentier and Venetz, and with his insatiable appetite and that faculty of assimilation which he possessed in such a wonderful degree, he digested the whole doctrine of the glaciers in a few weeks.”

In July, 1837, Agassiz presented as his presidential address before the Helvetic Society his memorable “Discours de Neuchâtel,” which was “the starting point of all that has been written on the Ice-age,”—a term coined at the time by his friend Schimper, a botanist. The first part of this address is reprinted in French in Marcou’s book on Agassiz. The address was received with astonishment, much incredulity, and indifference. Among the listeners was the great German geologist Von Buch, who “was horrified, and with his hands raised towards the sky, and his head bowed to the distant Bernese Alps, exclaimed: ‘O Sancte de Saussure, ora pro nobis!’” Even De Charpentier “was not gratified to see his glacial theory mixed with rather uncalled for biological problems, the connection of which with the glacial age was more than problematic.” Agassiz was then a Cuvierian catastrophist and creationist, and advanced the idea of a series of glacial ages to explain the destruction of the geologic succession of faunas! Curiously, this theory was at once accepted by the American paleontologist T. A. Conrad (35, 239, 1839).

The classics in glacial geology are Agassiz’s Etudes sur les Glaciers, 1840, and De Charpentier’s Essai sur les Glaciers, 1841. Of the latter book, Marcou states that it has been said: “It is impossible to be truly a geologist without having read and studied it.” In the English language there is Tyndall’s Glaciers of the Alps, 1860.

The progress of the ideas in regard to Pleistocene glaciation is presented in the following chapter by H. E. Gregory.

Older Glacial Climates.—Hardly had the Pleistocene glacial climate been proved, when geologists began to point out the possibility of even earlier ones. An enthusiastic Scotch writer, Sir Andrew Ramsay, in 1855 described certain late Paleozoic conglomerates of middle England, which he said were of glacial origin, but his evidence, though never completely gainsaid, has not been generally accepted. In the following year, an Englishman, Doctor W. T. Blanford, said that the Talchir conglomerates of central and southern India were of glacial origin, and since then the evidence for a Permian glacial climate has been steadily accumulating. Africa is the land of tillites, and here in 1870 Sutherland pointed out that the conglomerates of the Karroo formation were of glacial origin. Australia also has Permian glacial deposits, and they are known widely in eastern Brazil, the Falkland Islands, the vicinity of Boston, and elsewhere. So convincing is this testimony that all geologists are now ready to accept the conclusion that a glacial climate was as wide-spread in early Permian time as was that of the Pleistocene.[^[3]]

In South Africa, beneath the marine Lower Devonian, occurs the Table Mountain series, 5000 feet thick. The series is essentially one of quartzites, with zones of shales or slates and with striated pebbles up to 15 inches long. The latter occur in pockets and seem to be of glacial origin. There are here no typical tillites, and no striated undergrounds have so far been found. While the evidence of the deposits appears to favor the conclusion that the Table Mountain strata were laid down in cold waters with floating ice derived from glaciers, it is as yet impossible to assign these sediments a definite geologic age. They are certainly not younger than the Lower Devonian, but it has not yet been established to what period of the early Paleozoic they belong.

In southeastern Australia occur tillites of wide distribution that lie conformably beneath, but sharply separated from the fossiliferous marine Lower Cambrian strata. David (1907), Howchin (1908), and other Australian geologists think they are of Cambrian time, but to the writer they seem more probably late Proterozoic in age. In arctic Norway Reusch discovered unmistakable tillites in 1891, and this occurrence was confirmed by Strahan in 1897. It is not yet certainly known what their age is, but it appears to be late Proterozoic rather than early Paleozoic. Other undated Proterozoic tillites occur in China (Willis and Blackwelder 1907), Africa (Schwarz 1906), India (Vredenburg 1907), Canada (Coleman 1908), and possibly in Scotland.

The oldest known tillites are described by Coleman in 1907, and occur at the base of the Lower Huronian or in early Proterozoic time. They extend across northern Ontario for 1000 miles, and from the north shore of Lake Huron northward for 750 miles.

Fossils as Climatic Indexes.—Paleontologists have long been aware that variations in the climates of the past are indicated by the fossils, and Neumayr in 1883 brought the evidence together in his study of climatic zones mentioned elsewhere. Plants, and corals, cephalopods, and foraminifers among marine animals, have long been recognized as particularly good “life thermometers.” In fact, all fossils are climatic indicators to some extent, and a good deal of evidence concerning paleometeorology has been discerned in them. This evidence is briefly stated in the paper by Schuchert already alluded to, and in W. D. Matthew’s Climate and Evolution, 1915.

Sediments as Climatic Indexes.—Johannes Walther in the third part of his Einleitung—Lithogenesis der Gegenwart, 1894—is the first one to decidedly direct attention to the fact that the sediments also have within themselves a climatic record. In America Joseph Barrell has since 1907 written much on the same subject. On the other hand, the periodic floodings of the continents by the oceans, and the making of mountains, due to the periodic shrinkage of the earth, as expressed in T. C. Chamberlin’s principle of diastrophism and in his publications since 1897, are other criteria for estimating the climates of the past.

Conclusions.—In summation of this subject Schuchert says:

“The marine ‘life thermometer’ indicates vast stretches of time of mild to warm and equable temperatures, with but slight zonal differences between the equator and the poles. The great bulk of marine fossils are those of the shallow seas, and the evolutionary changes recorded in these ‘medals of creation’ are slight throughout vast lengths of time that are punctuated by short but decisive periods of cooled waters and great mortality, followed by quick evolution, and the rise of new stocks. The times of less warmth are the miotherm and those of greater heat the pliotherm periods of Ramsay.

On the land the story of the climatic changes is different, but in general the equability of the temperature simulates that of the oceanic areas. In other words, the lands also had long-enduring times of mild to warm climates. Into the problem of land climates, however, enter other factors that are absent in the oceanic regions, and these have great influence upon the climates of the continents. Most important of these is the periodic warm-water inundation of the continents by the oceans, causing insular climates that are milder and moister. With the vanishing of the floods somewhat cooler and certainly drier climates are produced. The effects of these periodic floods must not be underestimated, for the North American continent was variably submerged at least seventeen times, and over an area of from 154,000 to 4,000,000 square miles.

When to these factors is added the effect upon the climate caused by the periodic rising of mountain chains, it is at once apparent that the lands must have had constantly varying climates. In general the temperature fluctuations seem to have been slight, but geographically the climates varied between mild to warm pluvial, and mild to cool arid. The arid factor has been of the greatest import to the organic world of the lands. Further, when to all of these causes is added the fact that during emergent periods the formerly isolated lands were connected by land bridges, permitting intermigration of the land floras and faunas, with the introduction of their parasites and parasitic diseases, we learn that while the climatic environment is of fundamental importance it is not the only cause for the more rapid evolution of terrestrial life....

Briefly, then, we may conclude that the markedly varying climates of the past seem to be due primarily to periodic changes in the topographic form of the earth’s surface, plus variations in the amount of heat stored by the oceans. The causation for the warmer interglacial climates is the most difficult of all to explain, and it is here that factors other than those mentioned may enter.

Granting all this, there still seems to lie back of all these theories a greater question connected with the major changes in paleometeorology. This is: What is it that forces the earth’s topography to change with varying intensity at irregularly rhythmic intervals?... Are we not forced to conclude that the earth’s shape changes periodically in response to gravitative forces that alter the body-form?”

Evolution.

Modern evolution, or the theory of life continuously descending from life with change, may be said to have had its first marked development in Comte de Buffon (1707–1788), a man of wealth and station, yet an industrious compiler, a brilliant writer, and a popularizer of science. He was not, however, a true scientific investigator, and his monument to fame is his Histoire Naturelle, in forty-four volumes, 1749–1804. A. S. Packard in his book on Lamarck, his Life and Work, 1901, concludes in regard to Buffon as follows:

“The impression left on the mind, after reading Buffon, is that even if he threw out these suggestions and then retracted them, from fear of annoyance or even persecution from the bigots of his time, he did not himself always take them seriously, but rather jotted them down as passing thoughts.... They appeared thirty-four years before Lamarck’s theory, and though not epoch-making, they are such as will render the name of Buffon memorable for all time.”

Chevalier de Lamarck (1744–1829) may justly be regarded as the founder of the doctrine of modern evolution. Previous to 1794 he was a believer in the fixity of species, but by 1800 he stood definitely in favor of evolution. Locy in his Biology and its Makers, 1908, states his theories in the following simplified form:

“Variations of organs, according to Lamarck, arise in animals mainly through use and disuse, and new organs have their origin in a physiological need. A new need felt by the animal [due to new conditions in its life, or the environment] expresses itself on the organism, stimulating growth and adaptations in a particular direction.”

To Lamarck, “inheritance was a simple, direct transmission of those superficial changes that arise in organs within the lifetime of an individual owing to use and disuse.” This part of his theory has come to be known as “the inheritance of acquired characters.”

Georges Cuvier (1769–1832), a peer of France, was a decided believer in the fixity of species and in their creation through divine acts. In 1796 he began to see that among the fossils so plentiful about Paris many were of extinct forms, and later on that there was a succession of wholly extinct faunas. This at first puzzling phenomenon he finally came to explain by assuming that the earth had gone through a series of catastrophes, of which the Deluge was the most recent but possibly not the last. With each catastrophe all life was blotted out, and a new though improved set of organisms was created by divine acts. The Cuvierian theory of catastrophism was widely accepted during the first half of the nineteenth century, and in America Louis Agassiz was long its greatest exponent. It was this theory and the dominance of the brilliant Cuvier, not only in science but socially as well, that blotted out the far more correct views of the more philosophical Lamarck, who held that life throughout the ages had been continuous and that through individual effort and the inheritance of acquired characters had evolved the wonderful diversity of the present living world.

In 1830 there was a public debate at Paris between Cuvier and Geoffroy Saint-Hilaire, the one holding to the views of the fixity of species and creation, the other that life is continuous and evolves into better adapted forms. Cuvier, a gifted speaker and the greatest debater zoology ever had, with an extraordinary memory that never failed him, defeated Saint-Hilaire in each day’s debate, although the latter was in the right.

A book that did a great deal to prepare the English-speaking people for the coming of evolution was “Vestiges of Creation,” published in 1844 by an unknown author. In Darwin’s opinion, “the work, from its powerful and brilliant style ... has done excellent service ... in thus preparing the ground for the reception of analogous views.” This book was recommended to the readers of the Journal (48, 395, 1845) with the editorial remark that “we cannot subscribe to all of the author’s views.”

We can probably best illustrate the opinions of Americans on the question of evolution just before the appearance of Darwin’s great work by directing attention to James D. Dana’s Thoughts on Species (24, 305, 1857). After reading this article and others of a similar nature by Agassiz, one comes to the opinion that unconsciously both men are proving evolution, but consciously they are firm creationists. It is astonishing that with their extended and minute knowledge of living organisms and their philosophic type of mind neither could see the true significance of the imperceptible transitions between some species, which if they do not actually pass into, at least shade towards, one another.

Dana speaks of “the endless diversities in individuals” that compose a species, and then states that a living species, like an inorganic one, “is based on a specific amount or condition of concentered force defined in the act or law of creation.” Species, he says, are permanent, and hybrids “cannot seriously trifle with the true units of nature, and at the best, can only make temporary variations.” “We have therefore reason to believe from man’s fertile intermixture, that he is one in species: and that all organic species are divine appointments which cannot be obliterated, unless by annihilating the individuals representing the species.”

Through the activities of the French the world was prepared for the reception of evolution, and now it was already in the minds of many advanced thinkers. In 1860 Asa Gray sent to the editor of the Journal (29, 1) an article by the English botanist, Joseph D. Hooker, entitled “On the Origination and Distribution of Species,” with these significant remarks:

“The essay cannot fail to attract the immediate and profound attention of scientific men.... It has for some time been manifest that a re-statement of the Lamarckian hypothesis is at hand. We have this, in an improved and truly scientific form, in the theories which, recently propounded by Mr. Darwin, followed by Mr. Wallace, are here so ably and altogether independently maintained. When these views are fully laid before them, the naturalists of this country will be able to take part in the interesting discussion which they will not fail to call forth.”

Hooker took up a study of the flora of Tasmania, of which the above cited article is but a chapter, with a view to trying out Darwin’s theory, and he now accepts it. He says, “Species are derivative and mutable.” “The limits of the majority of species are so undefinable that few naturalists are agreed upon them.”

Asa Gray had received from Darwin an advance copy of the book that was to revolutionize the thought of the world, and at once wrote for the Journal a Review of Darwin’s Theory on the Origin of Species by means of Natural Selection (29, 153, 1860). This is a splendid, critical but just, scientific review of Darwin’s epoch-making book. Evidently views similar to those, of the English scientist had long been in the mind of Gray, for he easily and quickly mastered the work. He is easy on Dana’s Thoughts on Species, which were idealistic and not in harmony with the naturalistic views of Darwin. On the other hand, he contrasts Darwin’s views at length with those of the creationists as exemplified by Louis Agassiz, and says “The widest divergence appears.”

Gray says in part:

“The gist of Mr. Darwin’s work is to show that such varieties are gradually diverged into species and genera through natural selection; that natural selection is the inevitable result of the struggle for existence which all living things are engaged in; and that this struggle is an unavoidable consequence of several natural causes, but mainly of the high rate at which all organic beings tend to increase.

Darwin is confident that intermediate forms must have existed; that in the olden times when the genera, the families and the orders diverged from their parent stocks, gradations existed as fine as those which now connect closely related species with varieties. But they have passed and left no sign. The geological record, even if all displayed to view, is a book from which not only many pages, but even whole alternate chapters have been lost out, or rather which were never printed from the autographs of nature. The record was actually made in fossil lithography only at certain times and under certain conditions (i.e., at periods of slow subsidence and places of abundant sediment); and of these records all but the last volume is out of print; and of its pages only local glimpses have been obtained. Geologists, except Lyell, will object to this,—some of them moderately, others with vehemence. Mr. Darwin himself admits, with a candor rarely displayed on such occasions, that he should have expected more geological evidence of transition than he finds, and that all the most eminent paleontologists maintain the immutability of species.

The general fact, however, that the fossil fauna of each period as a whole is nearly intermediate in character between the preceding and the succeeding faunas, is much relied on. We are brought one step nearer to the desired inference by the similar ‘fact,’ insisted on by all paleontologists, that fossils from two consecutive formations are far more closely related to each other, than are the fossils of two remote formations.

It is well said that all organic beings have been formed on two great laws; Unity of type, and Adaptation to the conditions of existence.... Mr. Darwin harmonizes and explains them naturally. Adaptation to the conditions of existence is the result of Natural Selection; Unity of type, of unity of descent.”

Gray’s article was soon followed by another one from Agassiz on Individuality and Specific Differences among Acalephs, but the running title is “Prof. Agassiz on the Origin of Species” (30, 142, 1860). Agassiz stoutly maintains his well known views, and concludes as follows:

“Were the transmutation theory true, the geological record should exhibit an uninterrupted succession of types blending gradually into one another. The fact is that throughout all geological times each period is characterized by definite specific types, belonging to definite genera, and these to definite families, referable to definite orders, constituting definite classes and definite branches, built upon definite plans. Until the facts of Nature are shown to have been mistaken by those who have collected them, and that they have a different meaning from that now generally assigned to them, I shall therefore consider the transmutation theory as a scientific mistake, untrue in its facts, unscientific in its method, and mischievous in its tendency.”

Dana, in reviewing Huxley’s well known book, Man’s Place in Nature (35, 451, 1863), holds that man is apart from brute nature because man exhibits “extreme cephalization” in that he has arms that no longer are used in locomotion but go rather with the head, and because he has a far higher mentality and speech. As for the Darwinian theory, the evidence, he says, “comes from lower departments of life, and is acknowledged by its advocates to be exceedingly scanty and imperfect.”

The growth of evolution is set forth in the Journal in Asa Gray’s article on Charles Darwin (24, 453, 1882), which speaks of the latter as “the most celebrated man of science of the nineteenth century,” and, in addition, as “one of the most kindly and charming, unaffected, simple-hearted, and lovable of men.” In regard to the rise of evolution in America, more can be had from Dana’s paper on Asa Gray (35, 181, 1888). Here we read, as a sequel to his Thoughts on Species, that the “paper may be taken, perhaps, as a culmination of the past, just as the new future was to make its appearance.” Finally, in this connection there should be mentioned O. C. Marsh’s paper on Thomas Henry Huxley (50, 177, 1895), wherein is recorded the latter’s share in the upbuilding of the evolutionary theory.

We have seen that originally Dana was a creationist, but in the course of his long and fruitful life he gradually became an evolutionist, and rather a Neo-Lamarckian than a Darwinian. This change may be traced in the various editions of his Manual of Geology, and in the last edition of 1895 he says his “speculative conclusions” of 1852 in regard to the origin of species are not in “accord with the author’s present judgment.” “The evidence in favor of evolution by variation is now regarded as essentially complete.” On the other hand, while man is “unquestionably” closely related in structure to the man-apes, yet he is not linked to them but stands apart, through “the intervention of a Power above Nature.... Believing that Nature exists through the will and ever-acting power of the Divine Being, and ... that the whole Universe is not merely dependent on, but actually is, the Will of one Supreme Intelligence, Nature, with Man as its culminant species, is no longer a mystery.”

In America most of the paleontologists are Neo-Lamarckian, a school that was developed independently by E. D. Cope (1840–1897) through the vertebrate evidence, and by Alpheus Hyatt (1838–1902) mainly on the evidence of the ammonites. They hold that variations and acquired characters arise through the effects of the environment, the mechanics of the organism resulting from the use and disuse of organs, etc. One of the leading exponents of this school is A. S. Packard, whose book on Lamarck, His Life and Work, 1901, fully explains the doctrines of the Neo-Lamarckians.

The Growth of Invertebrate Paleontology.

How and by whom paleontology has been developed has been fully stated in the Journal in a very clear manner by Professor Marsh in his memorable presidential address of 1879, History and Methods of Palæontological Discovery (18, 323, 1879), and by Karl von Zittel in his most interesting book, History of Geology and Palæontology, 1901. In this discussion we shall largely follow Marsh.

The science of paleontology has passed through four periods, the first of them the long Mystic period extending up to the beginning of the seventeenth century, when the idea that fossils were once living things was only rarely perceived. The second period was the Diluvial period of the eighteenth century, when nearly everyone regarded the fossils as remains of the Noachian deluge. With the beginnings of the nineteenth century there arose in western Europe the knowledge that fossils are the “medals of creation” and that they have a chronogenetic significance; also that life had been periodically destroyed through world-wide convulsions in nature. From about 1800 to 1860 was the time of the creationists and catastrophists, which may be known as the Catastrophic period. The fourth period began in 1860 with Darwin’s Origin of Species. Since that time the theory of evolution has pervaded all work in paleontology, and accordingly this time may be known as the Evolutionary period.

Mystic Period.—The Mystic period in paleontology begins with the Greeks, five centuries before the present era, and continues down to the beginning of the seventeenth century of our time. Some correctly saw that the fossils were once living marine animals, and that the sea had been where they now occur. Others interpreted fossil mammal bones as those of human giants, the Titans, but the Aristotelian view that they were of spontaneous generation through the hidden forces of the earth dominated all thought for about twenty centuries.

In the sixteenth century canals were being dug in Northern Italy, and the many fossils so revealed led to a fierce discussion as to their actual nature. Leonardo da Vinci (1452–1519) opposed the commonly accepted view of their spontaneous generation and said that they were the remains of once living animals and that the sea had been where they occur. “You tell me,” he said, “that Nature and the influence of the stars have formed these shells in the mountains; then show me a place in the mountains where the stars at the present day make shelly forms of different ages, and of different species in the same place.” However, nothing came of his teachings and those of his countryman Fracastorio (1483–1553), who further ridiculed the idea that they were the remains of the deluge. The first mineralogist, Agricola, described them as minerals—fossilia—and said that they arose in the ground from fatty matter set in fermentation by heat. Others said that they were freaks of nature. Martin Lister (1638–1711) figured fossils side by side with living shells to show that they were extinct forms of life. In the seventeenth century, and especially in Italy and Germany, many books were published on fossils, some with illustrations so accurate that the species can be recognized to-day. Finally, toward the close of this century the influence of Aristotle and the scholastic tendency to disputation came more or less to an end. Fossils were already to many naturalists once living plants and animals. Marsh states: “The many collections of fossils that had been brought together, and the illustrated works that had been published about them, were a foundation for greater progress, and, with the eighteenth century, the second period in the history of paleontology began.”

Diluvial Period.—During the eighteenth century many more books on fossils were published in western Europe, and now the prevalent explanation was that they were the remains of the Noachian deluge. For nearly a century theologians and laymen alike took this view, and some of the books have become famous on this account, but the diluvial views sensibly declined with the close of the eighteenth century.

The true nature of fossils had now been clearly determined. They were the remains of plants and animals, deposited long before the deluge, part in fresh water and part in the sea. “Some indicated a mild climate, and some the tropics. That any of these were extinct species, was as yet only suspected.” Yet before the close of the century there were men in England and France who pointed out that different formations had different fossils and that some of them were extinct. These views then led to many fantastic theories as to how the earth was formed—dreams, most of them have been called. Marsh says:

“The dominant idea of the first sixteen centuries of the present era was, that the universe was made for Man. This was the great obstacle to the correct determination of the position of the earth in the universe, and, later, of the age of the earth.... In a superstitious age, when every natural event is referred to a supernatural cause, science cannot live.... Scarcely less fatal to the growth of science is the age of Authority, as the past proves too well. With freedom of thought, came definite knowledge, and certain progress;—but two thousand years was long to wait.”

One of the most significant publications of this period was Linnæus’s Systema Naturæ, which appeared in 1735. In this work was introduced binomial nomenclature, or the system of giving each plant and animal species a generic and specific name, as Felis leo for the lion. The system was, however, not established until the tenth edition of the work in 1758, which became the starting point of zoological nomenclature. Since then there has been added another canon, the law of priority, which holds that the first name applied to a given form shall stand against all later names given to the same organism.

Catastrophic Period.—With the beginning of the nineteenth century there started a new era in paleontology, and this was the time when the foundations of the science were laid. The period continued for six decades, or until the time of the Origin of Species. Marsh says that now “method replaced disorder, and systematic study superseded casual observation.” Fossils were accurately determined, comparisons were made with living forms, and the species named according to the binomial system. However, every species, recent and extinct, was regarded as a separate creation, and because of the usually sharp separation of the superposed fossil faunas and floras, these were held to have been destroyed through a series of periodic catastrophes of which the Noachian deluge was the last.

Lamarck between 1802 and 1806 described the Tertiary shells of the Paris basin. Comparing them with the living forms, he saw that most of the fossils were of extinct species, and in this way he came to be the founder of modern invertebrate paleontology. He also maintained after 1801 that life has been continuous since its origin and that nature has been uniform in the course of its development. Marsh adds:

“His researches on the invertebrate fossils of the Paris Basin, although less striking, were not less important than those of Cuvier on the vertebrates; while the conclusions he derived from them form the basis of modern biology.”

“Lamarck was the prophetic genius, half a century in advance of his time.”

Cuvier established comparative anatomy and vertebrate paleontology, and was one of the first to point out that fossil animals are nearly all extinct forms. He came to the latter conclusion in 1796 through a study of fossil elephants found in Europe. “Cuvier enriched the animal kingdom by the introduction of fossil forms among the living, bringing all together into one comprehensive system.” This opened to him entirely new views respecting the theory of the earth, and he devoted more than twenty-five years to developing the theories of special creation and catastrophism, described in his Discourse on the Revolutions of the Surface of the Globe. “With all his knowledge of the earth, he could not free himself from tradition, and believed in the universality and power of the Mosaic deluge. Again, he refused to admit the evidence brought forward by his distinguished colleagues against the permanence of species, and used all his great influence to crush out the doctrine of evolution, then first proposed” (Marsh).

In England it was William Smith (1769–1839) who independently discovered the chronogenetic significance of fossils, and in their stratigraphic superposition indicated the way for the study of historical geology. He first published on this matter in 1799, but his completed statements came in works entitled “Strata identified by Organized Fossils,” 1816–1820, and “Stratigraphical System of Organized Fossils,” 1817.

Invertebrate paleontology in America during the Catastrophic period had its beginning in Lesueur, who in 1818 described the Ordovician gastropod Maclurites magna. All of the paleontologists of this time were satisfied to describe species and genera and to ascertain in a broad way the stratigraphic significance of the fossil faunas and floras. James Hall in 1854 (17, 312) knew of 1588 species, described and undescribed, in the New York system, while in England Morris listed in that year 8300 Paleozoic forms. In 1856 Dana recites the known fossil species as follows (22, 333): The whole number of known American species of animals of the Permian to Recent is about 2000; while in Britain and Europe, there were over 20,000 species. In the Permian we have none, while Europe has over 200 species. In the Triassic we have none, Europe 1000 species; Jurassic 60, Europe over 4000; Cretaceous 350 to 400, Europe about 6000; Tertiary hardly 1500, Europe about 8000. Since that time nearly all of the larger American Paleozoic faunas have been developed, but there are thousands of species yet to be described. Who the more prominent American paleontologists of this period were has been told in the section on the development of the geological column.

The grander paleontologic results of the Catastrophic period have been so well stated by Marsh that it is worth our while to repeat them here:

“It had now been proved beyond question that portions at least of the earth’s surface had been covered many times by the sea, with alternations of fresh water and of land; that the strata thus deposited were formed in succession, the lowest of the series being the oldest; that a distinct succession of animals and plants had inhabited the earth during the different geological periods; and that the order of succession found in one part of the earth was essentially the same in all. More than 30,000 new species of extinct animals and plants had now been described. It had been found, too, that from the oldest formations to the most recent, there had been an advance in the grade of life, both animal and vegetable, the oldest forms being among the simplest, and the higher forms successively making their appearance.

It had now become clearly evident, moreover, that the fossils from the older formations were all extinct species, and that only in the most recent deposits were there remains of forms still living.... Another important conclusion reached, mainly through the labors of Lyell, was, that the earth had not been subjected in the past to sudden and violent revolutions; but the great changes wrought had been gradual, differing in no essential respect from those still in progress. Strangely enough, the corollary to this proposition, that life, too, had been continuous on the earth, formed at that date no part of the common stock of knowledge. In the physical world, the great law of ‘correlation of forces’ had been announced, and widely accepted; but in the organic world, the dogma of the miraculous creation of each separate species still held sway.”

Evolutionary Period.—This period begins with 1860 and the publication of Darwin’s Origin of Species (late in 1859). It is the period of modern paleontology, and is dominated by the belief that universal laws pervade not only inorganic matter, but all life as well. Louis Agassiz had been in America fourteen years when Darwin’s book appeared, and his wonderful influence in bringing the zoology of our country to a high stand and the further influence he exerted through his students was bound to react beneficially on invertebrate paleontology. Shortly after the beginning of this period, or in 1867, Alpheus Hyatt, one of Agassiz’s students, began to apply the study of embryology to fossil cephalopods, showing clearly that these shells retain a great deal of their growth stages or ontogeny. This method of study was then followed by R. T. Jackson, C. E. Beecher, and J. P. Smith, and has been productive of natural classifications of the Cephalopoda, Brachiopoda, Trilobita, and Echinoidea.

The dominant invertebrate paleontologist of this period was of course James Hall, who described about 5000 species of American Paleozoic fossils. He also built up the New York State Museum, while around his private collections of fossils have been developed the American Museum of Natural History in New York City and the Walker Museum at the University of Chicago. In his most important laboratory of paleontology at Albany, there have been trained either wholly or in part the following paleontologists: F. B. Meek, C. A. White, R. P. Whitfield, C. D. Walcott, C. E. Beecher, John M. Clarke, and Charles Schuchert.

In Canada, through the work of the Geological Survey of the Dominion, came the paleontologists Elkanah Billings and, later on, J. F. Whiteaves. The “father of Canadian paleontology,” Sir William Dawson, who developed independently, was active in all branches of the science and did much to unravel the geology of eastern Canada. No organism has been more discussed and more often rejected and accepted as a fossil than his “dawn animal of Canada,” Eozoon canadense, first described in 1865. His son, George M. Dawson, was one of the directors of the Geological Survey of Canada. Finally the extensive paleontology of the Cambrian of Canada was worked out by another self-made paleontologist, G. F. Matthew.

Paleobotany.—American paleobotany was developed during this, the fourth period, through the state and national surveys, first in Leo Lesquereux, a Swiss student induced by Agassiz to come to America, and in J. S. Newberry. The second generation of paleobotanists is represented by Lester F. Ward and W. N. Fontaine, and the third generation, the present workers, includes F. H. Knowlton, David White, Arthur Hollick, and E. W. Berry. A new line of paleobotanical work, the histology of woody but pseudomorphous remains, has been developed by G. R. Wieland.

The grander results of the study of paleontology during the evolutionary period may be summed up with the conclusions of Marsh:

“One of the main characteristics of this epoch is the belief that all life, living and extinct, has been evolved from simple forms. Another prominent feature is the accepted fact of the great antiquity of the human race. These are quite sufficient to distinguish this period sharply from those that preceded it.”

Charles Darwin’s work at once aroused attention, and brought about in scientific thought a revolution which “has influenced paleontology as extensively as any other department of science.... In the [previous period] species were represented independently by parallel lines; in the present period, they are indicated by dependent, branching lines. The former was the analytic, the latter is the synthetic period.”

Synthetic Period.—What is to be the next trend in paleontology? Clearly it is to be the Synthetic period, one that Marsh in 1879 indicated in these words: “But if we are permitted to continue in imagination the rapidly converging lines of research pursued to-day, they seem to meet at the point where organic and inorganic nature become one. That this point will yet be reached, I cannot doubt.”

This Synthetic period, foreshadowed also in Herbert Spencer’s Synthetic Philosophy, has not yet arrived, but before long another great leader will appear. We have the prophecy of his coming in such books as The Fitness of the Environment, by Lawrence J. Henderson, 1913; The Origin and Nature of Life, by Benjamin Moore, 1913; The Organism as a Whole, by Jacques Loeb, 1916; and The Origin and Evolution of Life, by Henry F. Osborn, 1917.

In all nature, inorganic and organic, there is continuity and consistency, beauty and design. We are beginning to see that there are eternal laws, ever interacting and resulting in progressive and regressive evolutions. The realization of these scientific revelations kindles in us a desire for more knowledge, and the grandest revelations are yet before us in the synthesis of the sciences.

Notes.

[3]. For more detail in regard to these tillites and the older ones see Climates of Geologic Time, by Charles Schuchert, being Chapter XXI in Huntington’s Climatic Factor as Illustrated in Arid America, Publication No. 192 of the Carnegie Institution of Washington, 1914. Also Arthur P. Coleman’s presidential address before the Geological Society of America in 1915, Dry Land in Geology, published in the Society’s Bulletin, 27, 175, 1916.

III
A CENTURY OF GEOLOGY.—STEPS OF PROGRESS IN THE INTERPRETATION OF LAND FORMS

By HERBERT E. GREGORY

The essence of physiography is the belief that land forms represent merely a stage in the orderly development of the earth’s surface features; that the various dynamic agents perform their characteristic work throughout all geologic time. The formulation of principle and processes of earth sculpture was, therefore, impossible on the hypothesis of a ready-made earth whose features were substantially unchangeable, except when modified by catastrophic processes. In 1821, J. W. Wilson wrote in the Journal: “Is it not the best theory of the earth, that the Creator, in the beginning, at least at the general deluge, formed it with all its present grand characteristic features?”[^[4]] If so, a search for causes is futile, and the study of the work performed by streams and glaciers and wind is unprofitable. The belief in the Deluge as the one great geological event in the history of the earth has brought it about that the speculations of Aristotle, Herodotus, Strabo, and Ovid, and the illustrious Arab, Avicenna (980–1037), unchecked by appeal to facts but also unopposed by priesthood or popular prejudice, are nearer to the truth than the intolerant controversial writings of the intellectual leaders whose touchstone was orthodoxy. A few thinkers of the sixteenth century revolted against the interminable repetition of error, and Peter Severinus (1571) advised his students: “Burn up your books ... buy yourselves stout shoes, get away to the mountains, search the valleys, the deserts, the shores of the seas.... In this way and no other will you arrive at a knowledge of things.” But the thoroughgoing “diluvialist” who believed that a million species of animals could occupy a 450–foot Ark, but not that pebbles weathered from rock or that rivers erode, had no use for his powers of observation.

Sporadic germs of a science of land forms scattered through the literature of the seventeenth and eighteenth centuries found an unfavorable environment and produced inconspicuous growths. Even their sponsors did little to cultivate them. Steno (1631–1687) mildly suggested that surface sculpturing, particularly on a small scale, is largely the work of running water, and Guettard (1715–1786), a truly great mind, grasped the fundamental principles of denudation and successfully entombed his views as well as his reputation in scores of books and volumes of cumbrous diffuse writing.

At the beginning of the nineteenth century a sufficient body of principles had been established to justify the recognition of an earth science, geology, and the 195 volumes of the Journal thus far published carry a large part of the material which has won approval for the new science and given prominence to American thought. From the pages in the Journal, the progress of geology may be illustrated by tracing the fluctuation in the development of fact and theory as relates to valleys and glacial features, the subjects to which this chapter is devoted.

The Interpretation of Valleys.

The Pioneers.

Desmarest (1725–1815) might be styled the father of physiography. By concrete examples and sound induction he established (1774) the doctrine that the valleys of central France are formed by the streams which occupy them. He also made the first attempt to trace the history of a landscape through its successive stages on the basis of known causes. His methods and reasoning are practically identical with those of Dutton working in the ancient lavas of New Mexico; and Whitney’s description of the Table Mountains of California might well have appeared in Desmarest’s memoirs.[^[5]] The teachings of Desmarest were strengthened and expanded by DeSaussure (1740–1799), the sponsor for the term, “Geology,” (1779) who saw in the intimate relation of Alpine streams and valleys the evidence of erosion by running water (1786).

The work of these acknowledged leaders of geological thought attracted singularly little attention on the Continent, and Lamarck’s volume on denudation (Hydrogéologie), which appeared in 1802, although an important contribution, sank out of sight. But the seed of the French school found fertile ground in Edinburgh, the center of the geological world during the first quarter of the nineteenth century. Hutton’s “Theory of the Earth, with Proofs and Illustrations,” in which the guidance of DeSaussure and Desmarest is gratefully acknowledged, appeared in 1795. The original publication aroused only local interest, but when placed in attractive form by Playfair’s “Illustrations of the Huttonian Theory” (1802), the problem of the origin and development of land forms assumed a commanding position in geological thought. Hutton was peculiarly fortunate in his environment. He had the support and assistance of a group of able scientific colleagues as well as the bitter opposition of Jameson and of the defenders of orthodoxy. His views were discussed in scientific publications and found their way to literary and theological journals. Hutton’s conception of the processes of land sculpture—slow upheaving and slow degradation of mountains, differential weathering, and the carving of valleys by streams—has a very modern aspect. Playfair’s book would scarcely be out of place in a twentieth century class room. The following paragraphs are quoted from it:[^[6]]

“... A river, of which the course is both serpentine and deeply excavated in the rock, is among the phenomena, by which the slow waste of the land, and also the cause of that waste, are most directly pointed out.

The structure of the vallies among mountains, shews clearly to what cause their existence is to be ascribed. Here we have first a large valley, communicating directly with the plain, and winding between high ridges of mountains, while the river in the bottom of it descends over a surface, remarkable, in such a scene, for its uniform declivity. Into this, open a multitude of transverse or secondary vallies, intersecting the ridges on either side of the former, each bringing a contribution to the main stream, proportioned to its magnitude; and, except where a cataract now and then intervenes, all having that nice adjustment in their levels, which is the more wonderful, the greater the irregularity of the surface. These secondary vallies have others of a smaller size opening into them; and, among mountains of the first order, where all is laid out on the greatest scale, these ramifications are continued to a fourth, and even a fifth, each diminishing in size as it increases in elevation, and as its supply of water is less. Through them all, this law is in general observed, that where a higher valley joins a lower one, of the two angles which it makes with the latter, that which is obtuse is always on the descending side; ... what else but the water itself, working its way through obstacles of unequal resistance, could have opened or kept up a communication between the inequalities of an irregular and alpine surface....

... The probability of such a constitution [arrangement of valleys] having arisen from another cause, is, to the probability of its having arisen from the running of water, in such a proportion as unity bears to a number infinitely great.

... With Dr. Hutton, we shall be disposed to consider those great chains of mountains, which traverse the surface of the globe, as cut out of masses vastly greater, and more lofty than any thing that now remains.

From this gradual change of lakes into rivers, it follows, that a lake is but a temporary and accidental condition of a river, which is every day approaching to its termination; and the truth of this is attested, not only by the lakes that have existed, but also by those that continue to exist.”

Steps Backward.

Even Hutton’s clear reasoning, firmly buttressed by concrete examples, was insufficient to overcome the belief in ready-made or violently formed valleys and original corrugations and irregularities of mountain surface. The pages of the Journal show that the principles laid down by Playfair were too far in advance of the times to secure general acceptance. In the first volume of the Journal, the gorge of the French Broad River is assigned by Kain to “some dreadful commotion in nature which probably shook these mountains to their bases,”[^[7]] and the gorge of the lower Connecticut is considered by Hitchcock (1824)[^[8]] as a breach which drained a series of lakes “not many centuries before the settlement of this country.” The prevailing American and English view for the first quarter of the nineteenth century is expressed in the reviews in this Journal, where the well-known conclusions of Conybeare and Phillips that streams are incompetent to excavate valleys are quoted with approval and admiration is expressed for Buckland’s famous “Reliquiæ Diluvianæ,” a 300–page quarto volume devoted to proof of a deluge. The professor at Yale, Silliman, and the professor at Oxford, Buckland, saw that an acceptance of Hutton’s views involved a repudiation of the Biblical flood, and much space is devoted to combating these “erroneous” and “unscientific” views. For example, Buckland says:[^[9]]

“... The general belief is, that existing streams, avalanches and lakes, bursting their barriers, are sufficient to account for all their phenomena, and not a few geologists, especially those of the Huttonian school, at whose head is Professor Playfair, have till recently been of this opinion.... But it is now very clear to almost every man, who impartially examines the facts in regard to existing vallies, that the causes now in action, mentioned above, are altogether inadequate to their production; nay, that such a supposition would involve a physical impossibility. We do not believe that one-thousandth part of our present vallies were excavated by the power of existing streams.... In very many cases of large rivers, it is found, that so far from having formed their own beds, they are actually in a gradual manner filling them up.

Again; how happens it that the source of a river is frequently below the head of a valley, if the river excavated that valley?

The most powerful argument, however, in our opinion, against the supposition we are combating, is the phenomena of transverse and longitudinal valleys; both of which could not possibly have been formed by existing streams.”

Phillips writes in 1829:[^[10]] “The excavation of valleys can be ascribed to no other cause than a great flood of water which overtopped the hills, whose summits those vallies descend.”

Faith in Noah’s flood as the dominant agent of erosion rapidly lost ground through the teaching of Lyell after 1830, but the theory of systematic development of landscapes by rivers gained little. In fact, Scrope in 1830,[^[11]] in showing that the entrenched meanders of the Moselle prove gradual progressive stream work, was in advance of his English contemporary. Judged by contributions to the Journal, Lyell’s teaching served to standardize American opinion of earth sculpture somewhat as follows: The ocean is the great valley maker, but rivers also make them; the position of valleys is determined by original or renewed surface inequalities or by faulting; exceptional occurrences—earthquakes, bursting of lakes, upheavals and depressions—have played an important part. Hayes (1839)[^[12]] thought that the surface of New York was essentially an upraised sea-bottom modified by erosion of waves and ocean currents. Sedgwick (1838)[^[13]] considered high-lying lake basins proof of valleys which were shaped under the sea. Many of the valleys in the Chilian Cordillera were thought by Darwin (1844) to have been the work of waves and tides, and water gaps are ascribed to currents “bursting through the range at those points where the strata have been least inclined and the height consequently is less.” Speaking of the magnificent stream-cut canyons of the Blue Mountains of New South Wales, gorges which lead to narrow exits through monoclines, Darwin says: “To attribute these hollows to alluvial action would be preposterous.”[^[14]]

The influence of structure in the formation of valleys is emphasized by many contributors to the Journal. Hildreth in 1836, in a valuable paper,[^[15]] which is perhaps the first detailed topographic description of drainage in folded strata, expresses the opinion that the West Virginia ridges and valleys antedated the streams and that water gaps though cut by rivers involve pre-existing lakes. Geddes (1826)[^[16]] denied that Niagara River cut its channel and speaks of valleys which “were valleys e’er moving spirit bade the waters flow.” Conrad (1839)[^[17]] discussed the structural control of the Mohawk, the Ohio, and the Mississippi, and Lieutenant Warren (1859)[^[18]] concluded that the Niobrara must have originated in a fissure. According to Lesley (1862)[^[19]] the course of the New River across the Great Valley and into the Appalachians “striking the escarpment in the face” is determined by the junction of anticlinal structures on the north with faulted monoclines toward the south; a conclusion in harmony with the views of Edward Hitchcock (1841)[^[17]] that major valleys and mountain passes are structural in origin and that even subordinate folds and faults may determine minor features. “Is not this a beautiful example of prospective benevolence on the part of the Deity, thus, by means of a violent fracture of primary mountains, to provide for easy intercommunication through alpine regions, countless ages afterwards!” The extent of the wandering from the guidance of DeSaussure and Playfair after the lapse of 50 years is shown by students of Switzerland. Alpine valleys to Murchison (1851) were bays of an ancient sea; Schlaginweit (1852) found regional and local complicated crustal movements a satisfactory cause, and Forbes (1863) saw only glaciers.

Valleys Formed by Rivers.

One strong voice before 1860 appears to have called Americans back to truths expounded by Desmarest and Hutton. Dana in 1850[^[20]] amply demonstrated that valleys on the Pacific Islands owe neither their origin, position or form to the sea or to structural factors. They are the work of existing streams which have eaten their way headwards. Even the valleys of Australia cited by Darwin as type examples of ocean work are shown to be products of normal stream work. Dana went further and gave a permanent place to the Huttonian idea that many bays, inlets, and fiords are but the drowned mouths of stream-made valleys. In the same volume in which these conclusions appeared, Hubbard (1850)[^[21]] announced that in New Hampshire the “deepest valleys are but valleys of erosion.” The theory that valleys are excavated by streams which occupy them was all but universally accepted after F. V. Hayden’s description[^[22]] of Rocky Mountain gorges (1862) and Newberry’s interpretation of the canyons of Arizona (1862); but the scientific world was poorly prepared for Newberry’s statement:[^[23]]

“Like the great canons of the Colorado, the broad valleys bounded by high and perpendicular walls belong to a vast system of erosion, and are wholly due to the action of water.... The first and most plausible explanation of the striking surface features of this region will be to refer them to that embodiment of resistless power—the sword that cuts so many geological knots—volcanic force. The Great Canon of the Colorado would be considered a vast fissure or rent in the earth’s crust, and the abrupt termination of the steps of the table lands as marking lines of displacement. This theory though so plausible, and so entirely adequate to explain all the striking phenomena, lacks a single requisite to acceptance, and that is truth.”

With such stupendous examples in mind, the dictum of Hutton seemed reasonable: “there is no spot on which rivers may not formerly have run.”

Denudation by Rivers.

The general recognition of the competency of streams to form valleys was a necessary prelude to the broader view expressed by Jukes (1862)[^[24]]

“The surfaces of our present lands are as much carved and sculptured surfaces as the medallion carved from the slab, or the statue sculptured from the block. They have been gradually reached by the removal of the rock that once covered them, and are themselves but of transient duration, always slowly wasting from decay.”

Contributions to the Journal between 1850 and 1870 reveal a tendency to accept greater degrees of erosion by rivers, but the necessary end-product of subaërial erosion—a plain—is first clearly defined by Powell in 1875.[^[25]] In formulating his ideas Powell introduced the term “base-level,” which may be called the germ word out of which has grown the “cycle of erosion,” the master key of modern physiographers. The original definition of base-level follows:

“We may consider the level of the sea to be a grand base-level, below which the dry lands cannot be eroded; but we may also have, for local and temporary purposes, other base-levels of erosion, which are the levels of the beds of the principal streams which carry away the products of erosion. (I take some liberty in using the term ‘level’ in this connection, as the action of a running stream in wearing its channel ceases, for all practical purposes, before its bed has quite reached the level of the lower end of the stream. What I have called the base-level would, in fact, be an imaginary surface, inclining slightly in all its parts toward the lower end of the principal stream draining the area through which the level is supposed to extend, or having the inclination of its parts varied in direction as determined by tributary streams.)”

Analysis of Powell’s view has given definiteness to the distinction between “base-level,” an imaginary plane, and “a nearly featureless plain,” the actual land surface produced in the last stage of subaërial erosion.

Following their discovery in the Colorado Plateau Province, denudation surfaces were recognized on the Atlantic slope and discussed by McGee (1888),[^[26]] in a paper notable for the demonstration of the use of physiographic methods and criteria in the solution of stratigraphic problems. Davis (1889)[^[27]] described the upland of southern New England developed during Cretaceous time, introducing the term “peneplain,” “a nearly featureless plain.” The short-lived opposition to the theory of peneplanation indicates that in America at least the idea needed only formulation to insure acceptance.

It is interesting to note that surfaces now classed as peneplains were fully described by Percival (1842),[^[28]] who assigned them to structure, and by Kerr (1880),[^[29]] who considered glaciers the agent. In Europe “plains of denudation” have been clearly recognized by Ramsay (1846), Jukes (1862), A. Geikie (1865), Foster and Topley (1865), Maw (1866), Wynne (1867), Whitaker (1867), Macintosh (1869), Green (1882), Richthofen (1882), but all of them were looked upon as products of marine work, and writers of more recent date in England seem reluctant to give a subordinate place to the erosive power of waves. Americans, on the other hand, have been thinking in terms of rivers, and the great contribution of the American school is not that peneplains exist, but that they are the result of normal subaërial erosion. More precise field methods during the past decade have revealed the fact that no one agent is responsible for the land forms classed as peneplains; that not only rivers and ocean, but ice, wind, structure, and topographic position must be taken into account.

The recognition of rivers as valley-makers and of the final result of stream work necessarily preceded an analysis of the process of subaërial erosion. The first and last terms were known, the intermediate terms and the sequence remained to be established. A significant contribution to this problem was made by Jukes (1862).[^[34]]

“... I believe that the lateral valleys are those which were first formed by the drainage running directly from the crests of the chains, the longitudinal ones being subsequently elaborated along the strike of the softer or more erodable beds exposed on the flanks of those chains.”

Powell’s discussion of antecedent and consequent drainage (1875) and Gilbert’s chapter on land sculpture in the Henry Mountain report (1880) are classics, and McGee’s contribution[^[30]] contains significant suggestions, but the master papers are by Davis,[^[31]] who introduces an analysis of land forms based on structure and age by the statement:

“Being fully persuaded of the gradual and systematic evolution of topographical forms it is now desired ... to seek the causes of the location of streams in their present courses; to go back if possible to the early date when central Pennsylvania was first raised from the sea, and trace the development of the several river systems then implanted upon it from their ancient beginning to the present time.”

That such a task could have been undertaken a quarter of a century ago and to-day considered a part of everyday field work shows how completely the lost ground of a half century has been regained and how rapid the advance in the knowledge of land sculpture since the canyons of the Colorado Plateau were interpreted.

Features Resulting from Glaciation.

The Problem Stated.

Early in the nineteenth century when speculation regarding the interior of the earth gave place in part to observations of the surface of the earth, geologists were confronted with perhaps the most difficult problem in the history of the science. As stated by the editor of the Journal in 1821:[^[32]]

“The almost universal existence of rolled pebbles, and boulders of rock, not only on the margin of the oceans, seas, lakes, and rivers; but their existence, often in enormous quantities, in situations quite removed from large waters; inland,—in high banks, embedded in strata, or scattered, occasionally, in profusion, on the face of almost every region, and sometimes on the tops and declivities of mountains, as well as in the vallies between them; their entire difference, in many cases, from the rocks in the country where they lie—rounded masses and pebbles of primitive rocks being deposited in secondary and alluvial regions, and vice versa; these and a multitude of similar facts have ever struck us as being among the most interesting of geological occurrences, and as being very inadequately accounted for by existing theories.”

The phenomena demanding explanation—jumbled masses of “diluvium,” polished and striated rock, bowlders distributed with apparent disregard of topography—were indeed startling. Even Lyell, the great exponent of uniformitarianism, appears to have lost faith in his theories when confronted with facts for which known causes seemed inadequate. The interest aroused is attested by 31 titles in the Journal during its first two decades, articles which include speculations unsupported by logic or fact, field observation unaccompanied by explanation, field observation with fantastic explanation, ex-cathedra pronouncements by prominent men, sound reasoning from insufficient data, and unclouded recognition of cause and effect by both obscure and prominent men. With little knowledge of glaciers, areal geology, or of structure and composition of drift, all known forces were called in: normal weathering, catastrophic floods, ocean currents, waves, icebergs, glaciers, wind, and even depositions from a primordial atmosphere (Chabier, 1823). Human agencies were not discarded. Speaking of a granite bowlder at North Salem, New York, described by Cornelius (1820)[^[33]] as resting on limestone, Finch (1824)[^[34]] says: “it is a magnificent cromlech and the most ancient and venerable monument which America possesses.” In the absence of a known cause, catastrophic agencies seem reasonable.

The Deluge.

In the seventh volume of the Journal (1824)[^[35]] we read:

“After the production of these regular strata of sand, clay, limestone, &c. came a terrible irruption of water from the north, or northwest, which in many places covered the preceding formations with diluvial gravel, and carried along with it those immense masses of granite, and the older rocks, which attest to the present day the destruction and ruin of a former world.”

Another author remarks:

“We find a mantle as it were of sand and gravel indifferently covering all the solid strata, and evidently derived from some convulsion which has lacerated and partly broken up those strata....”

The catastrophe favored by most geologists was floods of water violently released—“we believe,” says the editor, “that all geologists agree in imputing ... the diluvium to the agency of a deluge at one period or another.”[^[36]] Such conclusions rested in no small way upon Hayden’s well-known treatise on surficial deposits (1821),[^[37]] a volume which deserves a prominent place in American geological literature. Hayden clearly distinguished the topographic and structural features of the drift but found an adequate cause in general wide-spread currents which “flowed impetuously across the whole continent ... from north east to south west.” In reviewing Hayden’s book Silliman remarks:

“The general cause of these currents Mr. Hayden concludes to be the deluge of Noah. While no one will object to the propriety of ascribing very many, probably most of our alluvial features, to that catastrophe, we conceive that neither Mr. Hayden, nor any other man, is bound to prove the immediate physical cause of that vindictive infliction.

We would beg leave to suggest the following as a cause which may have aided in deluging the earth, and which, were there occasion, might do it again.

The existence of enormous caverns in the bowels of the earth, (so often imagined by authors,) appears to be no very extravagant assumption. It is true it cannot be proved, but in a sphere of eight thousand miles in diameter, it would appear in no way extraordinary, that many cavities might exist, which collectively, or even singly, might well contain much more than all our oceans, seas, and other superficial waters, none of which are probably more than a few miles in depth. If these cavities communicate in any manner with the oceans, and are (as if they exist at all, they probably are,) filled with water, there exist, we conceive, agents very competent to expel the water of these cavities, and thus to deluge, at any time, the dry land.”

The teachings of Hayden were favorably received by Hitchcock, Struder, and Hubbard, and many Europeans. They found a champion in Jackson, who states (1839):[^[38]]

“From the observations made upon Mount Ktaadn, it is proved, that the current did rush over the summit of that lofty mountain, and consequently the diluvial waters rose to the height of more than 5,000 feet. Hence we are enabled to prove, that the ancient ocean, which rushed over the surface of the State, was at least a mile in depth, and its transporting power must have been greatly increased by its enormous pressure.”

Gibson, a student of western geology, reaches the same conclusion (1836):[^[39]]

“That a wide-spread current, although not, as imagined, fed from an inland sea, once swept over the entire region between the Alleghany and the Rocky Mountains is established by plenary proof.”

Professor Sedgwick (1831) thought the sudden upheaval of mountains sufficient to have caused floods again and again. The strength of the belief in the Biblical flood, during the first quarter of the 19th century, may be represented by the following remarks of Phillips (1832):[^[40]]

“Of many important facts which come under the consideration of geologists, the ‘Deluge’ is, perhaps, the most remarkable; and it is established by such clear and positive arguments, that if any one point of natural history may be considered as proved, the deluge must be admitted to have happened, because it has left full evidence in plain and characteristic effects upon the surface of the earth.”

However, the theory of deluges, whether of ocean or land streams, did not hold the field unopposed. In 1823, Granger,[^[41]] an observer whose contributions to science total only six pages, speaks of the striæ on the shore of Lake Erie as

“having been formed by the powerful and continued attrition of some hard body.... To me, it does not seem possible that water under any circumstances, could have effected it. The flutings in width, depth, and direction, are as regular as if they had been cut out by a grooving plane. This, running water could not effect, nor could its operation have produced that glassy smoothness, which, in many parts, it still retains.”

Hayes and also Conrad expressed similar views in the Journal 16 years later.

The idea that ice was in some way concerned with the transportation of drift has had a curious history. The first unequivocal statement, based on reading and keen observation, was made in the Journal by Dobson in 1826:[^[42]]

“I have had occasion to dig up a great number of bowlders, of red sandstone, and of the conglomerate kind, in erecting a cotton manufactory; and it was not uncommon to find them worn smooth on the under side, as if done by their having been dragged over rocks and gravelly earth, in one steady position. On examination, they exhibit scratches and furrows on the abraded part; and if among the minerals composing the rock, there happened to be pebbles of feldspar, or quartz, (which was not uncommon,) they usually appeared not to be worn so much as the rest of the stone, preserving their more tender parts in a ridge, extending some inches. When several of these pebbles happen to be in one block, the preserved ridges were on the same side of the pebbles, so that it is easy to determine which part of the stone moved forward, in the act of wearing.

These bowlders are found, not only on the surface, but I have discovered them a number of feet deep, in the earth, in the hard compound of clay, sand, and gravel....

I think we cannot account for these appearances, unless we call in the aid of ice along with water, and that they have been worn by being suspended and carried in ice, over rocks and earth, under water.”

In Dobson’s day the hypothesis of “gigantic floods,” “debacles,” “resistless world-wide currents,” was so firmly entrenched that the voice of the observant layman found no hearers, and a letter from Dobson to Hitchcock written in 1837 and containing additional evidence and argument remained unpublished until Murchison, in 1842,[^[43]] paid his respects to the remarkable work of a remarkable man.[^[44]]

“I take leave of the glacial theory in congratulating American science in having possessed the original author of the best glacial theory, though his name had escaped notice; and in recommending to you the terse argument of Peter Dobson, a previous acquaintance with which might have saved volumes of disputation on both sides of the Atlantic.”

Glaciers vs. Icebergs.

The glacial theory makes its way into geological literature with the development of Agassiz (1837) of the views of Venetz (1833) and Charpentier (1834), that the glaciers of the Alps once had greater extent. The bold assumption was made that the surface of Europe as far south as the shores of the Mediterranean and Caspian seas was covered by ice during a period immediately preceding the present. The kernel of the present glacial theory is readily recognizable in these early works, but it is wrapped in a strange husk: it was assumed that the Alps were raised by a great convulsion under the ice and that the erratics slid to their places over the newly made declivities. The publication of the famous “Etudes sur les Glaciers” (1840), remarkable alike for its clarity, its sound inductions, and wealth of illustrations, brought the ideas of Agassiz more into prominence and inaugurated a 30–years’ war with the proponents of currents and icebergs. The outstanding objections to the theory were the requirement of a frigid climate and the demand for glaciers of continental dimensions; very strong objections, indeed, for the time when fossil evidence was not available, the great polar ice sheets were unexplored, and the distinction between till and waterlaid drift had not been established.

The glacial theory was cordially adopted by Buckland (1841)[^[45]] and in part by Lyell in England but viewed with suspicion by Sedgwick, Whewell, and Mantell. In America the response to the new idea was immediate. Hitchcock (1841)[^[46]] concludes an able discussion with the statement: “So remarkably does it solve most of the phenomena of diluvial action, that I am constrained to believe its fundamental principles to be founded in truth.”

The theory formed the chief topic of discussion at the third and fourth meetings of the Association of American Geologists and Naturalists (1842, 1843) under the lead of a committee on drift consisting of Emmons, W. B. Rogers, Vanuxem, Nicollet, Jackson, and J. L. Hayes. The result of these discussions was a curious reaction. Hitchcock complained that he “had been supposed to be an advocate for the unmodified glacial theory, but he had never been a believer in it,” and Jackson spoke for a number of men when he stated:[^[47]]

“This country exhibits no proofs of the glacial theory as taught by Agassiz but on the contrary the general bearing of the facts is against that theory.... Many eminent men incautiously embraced the new theory, which within two or three years from its promulgation, had been found utterly inadequate, and is now abandoned by many of its former supporters.”

Out of this symposium came also the strange contribution of H. D. Rogers (1844),[^[48]] who cast aside the teachings of deduction and observation and returned to the views of the Medievalists.

“If we will conceive, then, a wide expanse of waters, less perhaps than one thousand feet in depth, dislodged from some high northern or circumpolar basin, by a general lifting of that region of perhaps a few hundred feet, and an equal subsidence of the country south, and imagine this whole mass converted by earthquake pulsations of the breadth which such undulations have, into a series of stupendous and rapid-moving waves of translation, helped on by the still more rapid flexures of the floor over which they move, and then advert to the shattering and loosening power of the tremendous jar of the earthquake, we shall have an agent adequate in every way to produce the results we see, to float the northern ice from its moorings, to rip off, assisted with its aid, the outcrops of the hardest strata, to grind up and strew wide their fragments, to scour down the whole rocky floor, and, gathering energy with resistance, to sweep up the slopes and over the highest mountains.”

Because of the prominence of their author, Rogers’s views exerted some influence and seemingly received support from England through the elaborate mathematic discussions of Whewell (1848), who considered the drift as “irresistible proof of paroxysmal action,” and Hopkins (1852), who contended for “currents produced by repeated elevatory movements.”

After his arrival in America (1846), Agassiz’s influence was felt, and his paper on the erratic phenomena about Lake Superior (1850),[^[49]] in which he called upon the advocates of water-borne ice to point out the barrier which caused the current to subside, produced a salutary effect; yet Desor (1852)[^[50]] states that in the region described by Agassiz “the assumption [of a general ice cap] is no longer admissible,” and that the bowlders on Long Island “were transported on ice rafts along the sea shore and stranded on the ridges and eminences which were then shoals along the coast.” Twenty years of discussion were insufficient to establish the glacial theory either in Europe or America. The consensus of opinion among the more advanced thinkers in 1860 is expressed by Dana:[^[51]]

“In view of the whole subject, it appears reasonable to conclude that the Glacier theory affords the best and fullest explanation of the phenomena over the general surface of the continents, and encounters the fewest difficulties. But icebergs have aided beyond doubt in producing the results along the borders of the continents, across ocean-channels like the German Ocean and the Baltic, and possibly over great lakes like those of North America. Long Island Sound is so narrow that a glacier may have stretched across it.”

Papers in the Journal of 1860–70 show a prevailing belief in icebergs, but the evidence for land ice was accumulating as the deposits became better known, and in 1871 field workers speak in unmistakable tones:[^[52]]

“It is still a mooted question in American geology whether the events of the Glacial era were due to glaciers or icebergs.... American geologists are still divided in opinion, and some of the most eminent have pronounced in favor of icebergs.

Since, then, icebergs cannot pick up masses tons in weight from the bottom of a sea, or give a general movement southward to the loose material of the surface; neither can produce the abrasion observed over the rocks under its various conditions; and inasmuch as all direct evidence of the submergence of the land required for an iceberg sea over New England fails, the conclusion appears inevitable that icebergs had nothing to do with the drift of the New Haven region, in the Connecticut valley; and, therefore, that the Glacial era in central New England was a Glacier era.”

Matthew (1871)[^[53]] reached the same conclusion for the Lower Provinces of Canada. In spite of the increasing clarity of the evidence, the battle for the glacial theory was not yet won. The remaining opponents though few in number were distinguished in attainments. Dawson clung to the outworn doctrine until his death in 1899.

An interesting feature of the history of glacial theories is the calculation by Maclaren (1842)[^[54]] that the amount of water abstracted from the seas to form the hypothetical ice sheet would lower the ocean level 350 feet—an early form of the glacial control hypothesis (see Daly[^[55]]).

Extent of Glacial Drift.

By the middle of the nineteenth century, it was recognized that the “drift,” whatever its origin, was not of world-wide extent. In America its characteristic features were found best developed north of latitude 40 degrees; in Europe, the Alps, the Scottish Highlands, and Scandinavia were recognized as type areas. The limits were unassigned, partly because the field had not been surveyed, but largely because criteria for the recognition of drift had not been established. The well-known hillocks and ridges of “diluvium” and “alluvium” and “drift” of New Jersey and Ohio, and the mounds of the Missouri Cotou elaborately described by Catlin (1840)[^[56]] bore little resemblance to the walls of unsorted rock which stand as moraines bordering Alpine glaciers. The Orange sand of Mississippi was included in the drift by Hilgard (1866),[^[57]] and the gravels at Philadelphia by Hall (1876).[^[58]] Stevens (1873)[^[59]] described trains of glacial erratics at Richmond, Virginia, and William B. Rogers (1876)[^[60]] accounts for certain deposits in the Potomac, James, and Roanoke rivers by the presence of Pleistocene ice tongues or swollen glacial rivers, and remarks: “It is highly probable that glacial action had much to do with the original accumulation of the rocky debris on the flanks of the Blue Ridge, and in the Appalachian valleys beyond.” Kerr (1881)[^[61]] referred the ancient erosion surface of the Piedmont belt in North Carolina to glacial denudation, De la Beche compared the drift of Jamaica with that of New England, and Agassiz interpreted soils of Brazil as glacial.

The first detailed description and unequivocal interpretation of either terminal or recessional moraines is from the pen of Gilbert (1871),[^[62]] geologist of the Ohio Survey. In discussing the former outlet of Lake Erie through the Fort Wayne channel, Gilbert writes:

“The page of history recorded in these phenomena is by no means ambiguous. The ridges, or, more properly, the ridge which determines the courses of the St. Joseph and St. Marys rivers is a buried terminal moraine of the glacier that moved southwestward through the Maumee valley. The overlying Erie Clay covers it from sight, but it is shadowed forth on the surface of that deposit, as the ground is pictured through a deep and even canopy of snow. Its irregularly curved outline accords intimately with the configuration of the valley, and with the direction of the ice markings; its concavity is turned toward the source of motion; its greatest convexity is along the line of least resistance.

South of the St. Marys river are other and numerous moraines accompanied by glacial striæ. Their character and courses have not yet been studied; but their presence carries the mind back to an epoch of the cold period, when the margin of the icefield was farther south, and the glacier of the Maumee valley was merged in the general mass. As the mantle of ice grew shorter—and, in fact, at every stage of its existence—its margin must have been variously notched and lobed in conformity with the contour of the country, the higher lands being first laid bare by the encroaching secular summer. Early in the history of this encroachment the glacier of the Maumee valley constituted one of these lobes, and has recorded its form in the two moraines that I have described.”

Three years after the recognition of moraines in the Maumee valley, Chamberlin (1874)[^[63]] showed that the seemingly disorganized mounds and basins and ridges known as the Kettle range of Wisconsin is the terminal moraine of the Green Bay glacier. At an earlier date (1864) Whittlesey interpreted the kettles of the Wisconsin moraine as evidence of ice blocks from a melting glacier and presented a map showing the “southern limit of boulders and coarse drift.” In 1876 attention was called to the terminal moraine of New England by G. Frederick Wright, who assigns the honor of discovery to Clarence King.

With the observations of Gilbert, Chamberlin, and King in mind, the terminal moraine was traced by various workers across the United States and into Canada and the extent of glacial cover revealed. Following 1875 the pages of the Journal contain many contributions dealing with the origin and structure of moraines, eskers, kames, and drumlins. Before 1890 twenty-eight papers on the glacial phenomena of the Erie and Ohio basin alone had appeared. By 1900 substantial agreement had been reached regarding the significant features of the drift, the outline history of the Great Lakes had been written, and the way had been paved for stratigraphic studies of the Pleistocene, which bulk large in the pages of the Journal for the last two decades.

Epochs of Glaciation.

For a decade following the general acceptance of the glacial origin of “diluvium,” the deposits were embraced as “drift” and treated as the products of one long period of glacial activity, and throughout the controversy of iceberg and glacier the unity of the glacial period was unquestioned. Beds of peat and fossiliferous lacustrine deposits in Switzerland, England, and in America and the recognition of an “upper” and a “lower” diluvium by Scandinavian geologists suggested two epochs, and as the examples of such deposits increased in number and it became evident that the plant fossils represented forms demanding a genial climate and that the phenomena were seen in many countries, the belief grew that minor fluctuations or gradual recession of an ice sheet were inadequate to account for the phenomena observed.

It is natural that this problem should have found its solution in America, where the Pleistocene is admirably displayed, and where the State and Federal surveys were actively engaged in areal mapping. In 1883 Chamberlin[^[64]] presented his views under the bold title, “Preliminary Paper on the Terminal Moraine of the Second Glacial Epoch,” and the existence of deposits of two or more ice sheets and the features of interglacial periods were substantially established by the interesting debate in the Journal led by Chamberlin, Wright, Upham and Dana.[^[65]] Contributions since 1895 have been concerned with the degree rather than the fact of complexity, and continued study has resulted in the general recognition of five glacial stages in North America and four in Europe.

The Loess as a Glacial Deposit.

A curious side-product of the study of glaciation in North America is the controversy over the origin of loess. The interest aroused is indicated by scores of papers in American periodicals and State reports of the last quarter of the 19th century—papers which bear the names of prominent geologists.

The “loess” in the valley of the Rhine had long been known, but the subject assumed prominence by the publication in 1866 of Pumpelly’s Travels in China.[^[66]] Wide-spread deposits 200 to 1,000 feet thick were described as very fine-grained yellowish earth of distinctive structure without stratification but penetrated by innumerable tubes and containing land or fresh-water shells. Pumpelly considered these deposits lacustrine, a view which found general acceptance though combated by Kingsmill (1871),[^[67]] who argued for marine deposition. Baron Von Richthofen’s classic on China, which appeared in 1877, amplifies the observations of Pumpelly and marshals the evidence to support the hypothesis that the loess is wind-laid both on dry land and within ancient salt lakes. The conclusions of Von Richthofen were adopted by Pumpelly whose knowledge of the Chinese deposits, supplemented by studies in Missouri, of which State he was director of the Geological Survey in 1872–73, placed him in position to form a correct judgment. He says:[^[68]]

“Recognizing from personal observation the full identity of character of the loess of northern China, Europe and the Missouri Valley, I am obliged to reject my own explanation of the origin of the Chinese deposits, and to believe with Richthofen that the true loess, wherever it occurs, is a sub-aerial deposit, formed in a dry central region, and that it owes its structure to the formative influence of a steppe vegetation.

The one weak point of Richthofen’s theory is in the evident inadequacy of the current disintegration as a source of material. When we consider the immense area covered by loess to depths varying from 50 to 2,000 feet, and the fact that this is only the very finest portion of the product of rock-destruction, and again that the accumulation represents only a very short period of time, geologically speaking, surely we must seek a more fertile source of supply than is furnished by the current decomposition of rock surface.

It seems to me that there are two important sources: I. The silt brought by rivers, many of them fed by the products of glacial attrition flowing from the mountains into the central region. Where the streams sink away, or where the lakes which receive them have dried up, the finer products of the erosion of a large territory are left to be removed in dust storms.

II. The second ... source is the residuary products of a secular disintegration.”

The evidence presented by Pumpelly for the eolian origin of loess—structure, texture, composition, fossil content and topographic position—is complete, and to him belongs the credit for the correct interpretation of the Mississippi valley deposits. Unfortunately his contribution came at a time when the geologists of the central States were intent on tracing the paths and explaining the work of Pleistocene glaciers, and the belief was strong that loess was some phase of glacial work. Its position at the border of the Iowan drift so obviously suggests a genetic relation that the fossil evidence of steppe climate suggested by Binney in 1848[^[69]] was minimized. Students of Pleistocene geology in Minnesota, Iowa, Nebraska, Missouri, although less vigorous in expression, were substantially in agreement with Hilgard (1879).[^[70]] “The sum total of anomalous conditions required to sustain the eolian hypothesis partakes strongly of the marvellous.” The last edition of Dana’s Manual, 1894, and of LeConte’s Geology, 1896, the two most widely used text-books of their time, oppose the eolian theory, and Chamberlin, in 1897,[^[71]] states: “the aqueous hypothesis seems best supported so far as concerns the deposits of the Mississippi Valley and western Europe” (p. 795). Shimek, in papers published since 1896 has shown that aquatic and glacial conditions can not account for the loess fossils, and the return to the views of Pumpelly that the loess was deposited on land by the agency of wind in a region of steppe vegetation is now all but universal.

Glacial Sculpture.

Within the present generation sculpture by glaciers has received much attention and has involved a reconsideration of the ability of ice to erode which in turn involves a crystallization of views of the mechanics of moving ice. The evidence for glacier erosion has remained largely physiographic and rests on a study of land forms. In fact, the inadequacy of structural features or of river corrasion to account for flat-floored, steep-walled gorges, hanging valleys, and many lake basins, rather than a knowledge of the mechanics of ice has led to the present fairly general belief that glaciers are powerful agents of rock sculpture. The details of the process are not yet understood.

Erosion by glaciers enters the arena of active discussion in 1862–63. The possibility had been suggested by Esmark (1827) and by Dana (1849) in the description of fiords and by Hind (1855) with reference to the origin of the Great Lakes. It appears full-fledged in Ramsay’s classic, which was published simultaneously in England and in America.[^[72]] The argument runs as follows: There is a close association of ancient glaciers and lakes especially in mountains; glaciers are amply able to erode; evidences of faulting, special subsidence, river erosion, and marine erosion are absent from the lake basins of Switzerland and Great Britain. To quote Ramsay:

“It required a solid body grinding steadily and powerfully in direct and heavy contact with and across the rocks to scoop out deep hollows, the situations of which might either be determined by unequal hardness of the rocks, by extra weight of ice in special places, or by accidental circumstances, the clue to which is lost from our inability perfectly to reconstruct the original forms of the glaciers.”

“I believe with the Italian geologists, that all that the glaciers as a whole effected was only slightly to deepen these valleys and materially to modify their general outlines, and, further (a theory I am alone responsible for), to deepen them in parts more considerably when, from various causes, the grinding power of the ice was unusually powerful, especially where, as in the lowlands of Switzerland, the Miocene strata are comparatively soft.”

Whittlesey (1864)[^[73]] considered that the rock-bound lakes and narrow bays near Lake Superior were partly excavated by ice. LeConte (1875)[^[74]] records some significant observations in a pioneer paper on glacier erosion which has not received adequate recognition. He says:

“... I am convinced that a glacier, by its enormous pressure and resistless onward movement, is constantly breaking off large blocks from its bed and bounding walls. Its erosion is not only a grinding and scoring, but also a crushing and breaking. It makes by its erosion not only rock-meal, but also large rock-chips.... Its erosion is a constant process of alternate rough hewing and planing.

If Yosemite were unique, we might suppose that it was formed by violent cataclysms; but Yosemite is not unique in form and therefore probably not in origin. There are many Yosemites. It is more philosophical to account for them by the regular operation of known causes. I must believe that all these deep perpendicular slots have been sawn out by the action of glaciers; the peculiar verticality of the walls having been determined by the perpendicular cleavage structure.”... A lake in Bloody Canyon “is a pure rock basin scooped out by the glacier at this place.... These ridges [separating Hope, Faith, and Charity valleys] are in fact the lips of consecutive lake basins scooped out by ice.

... Water tends to form deep V-shaped canons, while ice produces broad valleys with lakes and meadows.... I know not how general these distinctions may be, but certainly the Coast range of this State is characterized by rounded summits and ridges, and deep V-shaped canons, while the high Sierras are characterized on the contrary by sharp, spire-like, comb-like summits, and broad valleys; and this difference I am convinced is due in part at least to the action of water on the one hand, and of ice on the other.”

King (1878)[^[75]] assigned to glacial erosion a commanding position in mountain sculpture. In regard to the Uintas, he says:

“Glacial erosion has cut almost vertically down through the beds carving immense amphitheatres with basin bottoms containing numerous Alpine lakes.... Post-glacial erosion has done an absolutely trivial work. There is not a particle of direct evidence, so far as I can see, to warrant the belief that these U-shaped canons were given their peculiar form by other means than the actual ploughing erosion of glaciers....”

These contributions from the Cordilleras corroborating the conclusions of Ramsay (1862), Tyndall (1862), Jukes (1862), Hector (1863), Logan (1863), Close (1870), and James Geikie (1875), made little impression. The views of Lyell (1833), Ball (1863), J. W. Dawson (1864), Falconer (1864), Studer (1864), Murchison (1864, 1870), Ruskin (1865), Rutimeyer (1869), Whymper (1871), Bonney (1873), Pfaff (1874), Gurlt (1874), Judd (1876), prevailed, and the conclusions of Davis in 1882[^[76]] fairly expressed the prevailing belief in Europe and in America:

“The amount of glacial erosion in the central districts has been very considerable, but not greatly in excess of pre-glacial soils and old talus and alluvial deposits. Most of the solid rock that was carried away came from ledges rather than from valleys; and glaciers had in general a smoothing rather than a roughening effect. In the outer areas on which the ice advanced it only rubbed down the projecting points; here it acted more frequently as a depositing than as an eroding agent.”

During the past quarter-century the cleavage in the ranks of geologists, brought about by Ramsay’s classic paper, has remained. Fairchild and others in America, Heim, Bonney, and Garwood in Europe argue for insignificant erosion by glaciers; and Gannet, Davis, Gilbert, Tarr in America followed by Austrian workers present evidence for erosion on a gigantic scale. A perusal of the voluminous literature in the Journal and elsewhere shows that the difference of opinion is in part one of terms, the amount of erosion rather than the fact of erosion; it also arises from failure to differentiate the work of mountain glaciers and continental ice sheets, of Pleistocene glaciers and their present diminished representatives. The irrelevant contribution of physicists has also made for confusion.

It is interesting to note that the criteria for erosion of valleys by glaciers has long been established and by workers in different countries. Ramsay (1862) in England outlined the problem and presented generalized evidence. Hector (1863) in New Zealand pointed out the significance of discordant drainage, the “hanging valleys” of Gilbert. The U-form, the broad lake-dotted floor, and the presence of cirques and the process of plucking were probably first described by LeConte (1873) in America. The truncation of valley spurs by glaciers pointed out by Studer in the Kerguelen Islands (1878) was used by Chamberlin (1883) as evidence of glacial scouring.

Conclusion.

During the past century many principles of land sculpture have emerged from the fog of intellectual speculation and unorganized observation and taken their place among generally accepted truths. Many of them are no longer subjects of controversy. Erosion has found its place as a major geologic agent and has given a new conception of natural scenery. Lofty mountains are no longer “ancient as the sun,” they are youthful features in process of dissection; valleys and canyons are the work of streams and glaciers; fiords are erosion forms; waterfalls and lakes are features in process of elimination; many plains and plateaus owe their form and position to long-continued denudation. Modern landscapes are no longer viewed as original features or the product of a single agent acting at a particular time, but as ephemeral forms which owe their present appearance to their age and the particular forces at work upon them as well as to their original structure.

It is interesting to note the halting steps leading to the present viewpoint, to find that decades elapsed between the formulation of a theory or the recording of significant facts and their final acceptance or rejection, and to realize that the organization of principles and observations into a science of physiography has been the work of the present generation. Progress has been conditioned by a number of factors besides the intellectual ability of individual workers.

The influence of locality is plainly seen. Convincing evidence of river erosion was obtained in central France, the Pacific Islands, and the Colorado Plateau—regions in which other causes were easily eliminated. Sculpture by glaciers passed beyond the theoretical stage when the simple forms of the Sierras and New Zealand Alps were described. The origin of loess was first discerned in a region where glacial phenomena did not obscure the vision. The complexity of the Glacial period asserted by geologists of the Middle West was denied by eastern students. The work of waves on the English coast impressed British geologists to such an extent that plains of denudation and inland valleys were ascribed to ocean work.

In the establishment of principles, the friendly interchange of ideas has yielded large returns. Many of the fundamental conceptions of earth sculpture have come from groups of men so situated as to facilitate criticism. It is impossible, even if desirable, to award individual credit to Venetz, Charpentier, and Agassiz in the formulation of the glacial theory; and the close association of Agassiz and Dana in New England and of Chamberlin and Irving in Wisconsin was undoubtedly helpful in establishing the theory of continental glaciation. From the intimate companionship in field and laboratory of Hutton, Playfair and Hope, arose the profound influence of the Edinburgh school, and the sympathetic cooperation of Powell, Gilbert, and Dutton has given to the world its classics in the genetic study of land forms.

The influence of ideas has been closely associated with clarity, conciseness, and attractiveness of presentation. Hutton is known through Playfair, Agassiz’s contributions to glacial geology are known to every student, while Venetz, Charpentier, and Hugi are only names. Cuvier’s discourses on dynamical geology were reprinted and translated into English and German, but Lamarck’s “Hydrogéologie” is known only to book collectors. The verbose works of Guettard, although carrying the same message as Playfair’s “Illustrations” and Desmarest’s “Memoirs,” are practically unknown, as is also Horace H. Hayden’s treatise (1821) on the drift of eastern North America. It has been well said that the world-wide influence of American physiographic teaching is due in no small part to the masterly presentations of Gilbert and Davis.

It is surprising to note the delays, the backward steps, and the duplication of effort resulting from lack of familiarity with the work of the pioneers. Sabine says in 1864:[^[77]]

“It often happens, not unnaturally, that those who are most occupied with the questions of the day in an advancing science retain but an imperfect recollection of the obligations due to those who laid the first foundations of our subsequent knowledge.”

The product of intellectual effort appears to be conditioned by time of planting and character of soil as well as by quantity of seed. For example: Erosion by rivers was as clearly shown by Desmarest as by Dana and Newberry 50 years later. Criteria for the recognition of ancient fluviatile deposits were established by James Deane in 1847 in a study of the Connecticut Valley Triassic. Agassiz’s proof that ice is an essential factor in the formation of till is substantially a duplication of Dobson’s observations (1826).

The volumes of the Journal with their very large number of articles and reviews dealing with geology show that the interpretation of land forms as products of subaërial erosion began in France and French Switzerland during the later part of the eighteenth century as a phase of the intellectual emancipation following the Revolution. Scotland and England assumed the leadership for the first half of the nineteenth century, and the first 100 volumes of the Journal show the profound influence of English and French teaching. In America, independent thinking, early exercised by the few, became general with the establishment of the Federal survey, the increase in university departments, geological societies and periodicals, and has given to Americans the responsibilities of teachers.

Bibliography.

(In the following list “this Journal” refers to the American Journal of Science.)

[4]. Wilson, J. W., Bursting of lakes through mountains, this Journal, 3, 253, 1821.

[5]. Whitney, J. D., Progress of the Geological Survey of California, this Journal, 38, 263–264, 1864.

[6]. Playfair, John, Illustrations of the Huttonian theory of the earth, Edinburgh, 1802.

[7]. Kain, J. H., Remarks on the mineralogy and geology of northwestern Virginia and eastern Tennessee, this Journal, 1, 60–67, 1819.

[8]. Hitchcock, Edward, Geology, etc., of regions contiguous to the Connecticut, this Journal, 7, 1–30, 1824.

[9]. Buckland, Wm., Reliquiæ diluvianæ, this Journal, 8, 150, 317, 1824.

[10]. Phillips, John, Geology of Yorkshire, this Journal, 21, 17–20, 1832.

[11]. Scrope, G. P., Excavation of valleys, Geol. Soc., London, No. 14, 1830.

[12]. Hayes, G. E., Remarks on geology and topography of western New York, this Journal, 35, 88–91, 1839.

[13]. Seventh Meeting of the British Association for the Advancement of Science, this Journal, 33, 288, 1838.

[14]. Darwin, Charles, Geological observations on the volcanic islands and parts of South America, etc., second part of the Voyage of the “Beagle,” during 1832–1836. London, 1844.

[15]. Hildreth, S. P., Observations, etc., valley of the Ohio, this Journal, 29, 1–148, 1836.

[16]. Geddes, James, Observations on the geological features of the south side of Ontario valley, this Journal, 11, 213–218, 1826.

[18]. Warren, G. K., Preliminary report of explorations in Nebraska and Dakota, this Journal, 27, 380, 1859.

[19]. Lesley, J. P., Observations on the Appalachian region of southern Virginia, this Journal, 34, review, 413–415, 1862.

[17]. Conrad, T. A., Notes on American geology, this Journal, 35, 237–251, 1839.

[20]. Dana, J. D., On denudation in the Pacific, this Journal, 9, 48–62, 1850.

——, On the degradation of the rocks of New South Wales and formation of valleys, this Journal, 9, 289–294, 1850.

[21]. Hubbard, O. P., On the condition of trap dikes in New Hampshire an evidence and measure of erosion, this Journal, 9, 158–171, 1850.

[22]. Hayden, F. V., Some remarks in regard to the period of elevation of the Rocky Mountains, this Journal, 33, 305–313, 1862.

[23]. Newberry, J. S., Colorado River of the West, this Journal, 33, review, 387–403, 1862.

[24]. Jukes, J. B., Address to the Geological Section of the British Association at Cambridge, Quart. Jour. Geol. Soc., 18, 1862, this Journal, 34, 439, 1862.

[25]. Powell, J. W., Exploration of the Colorado River of the West, 1875. For Powell’s preliminary article see this Journal, 5, 456–465, 1873.

[26]. McGee, W. J., Three formations of the Middle Atlantic slope, this Journal, 35, 120, 328, 367, 448, 1888.

[27]. Davis, W. M., Topographic development of the Triassic formation of the Connecticut Valley, this Journal, 37, 423–434, 1889.

[28]. Percival, J. G., Geology of Connecticut, 1842.

[29]. Kerr, W. C., Origin of some new points in the topography of North Carolina, this Journal, 21, 216–219, 1881.

[30]. McGee, W. J., The classification of geographic forms by genesis, Nat. Geogr. Mag., 1, 27–36, 1888.

[31]. Davis, W. M., The rivers and valleys of Pennsylvania, Nat. Geogr. Mag., 1, 183–253, 1889.

——, The rivers of northern New Jersey with notes on the classification of rivers in general, ibid., 2, 81–110, 1890.

[32]. Silliman, Benjamin, Notice of Horace H. Hayden’s geological essays, this Journal, 3, 49, 1821.

[33]. Cornelius, Elias, Account of a singular position of a granite rock, this Journal, 2, 200–201, 1820.

[34]. Finch, John, On the Celtic antiquities of America, this Journal, 7, 149–161, 1824.

[35]. Finch, John, Geological essay on the Tertiary formations in America, this Journal, 7, 31–43, 1824.

[36]. Conybeare and Phillips, Outlines of the geology of England and Wales, this Journal, 7, 210, 211, 1824.

[37]. Hayden, Horace H., Geological essays, 1–412, 1821, this Journal, 3, 47–57, 1821.

[38]. Jackson, C. T., Reports on the geology of the State of Maine, and on the public lands belonging to Maine and Massachusetts, this Journal, 36, 153, 1839.

[39]. Gibson, J. B., Remarks on the geology of the lakes and the valley of the Mississippi, this Journal, 29, 201–213, 1836.

[40]. Phillips, John, Geology of Yorkshire, this Journal, 21, 14–15, 1832.

[41]. Granger, Ebenezer, Notice of a curious fluted rock at Sandusky Bay, Ohio, this Journal, 6, 180, 1823.

[42]. Dobson, Peter, Remarks on bowlders, this Journal, 10, 217–218, 1826.

[43]. Murchison, R. I., Address at anniversary meeting of the Geological Society of London, this Journal, 43, 200–201, 1842.

[44]. Peter Dobson (1784–1878) came to this country from Preston, England, in 1809 and established a cotton factory at Vernon, Conn.

[45]. Buckland, W., On the evidence of glaciers in Scotland and the north of England, Proc. London Geol. Soc., 3, 1841.

[46]. Hitchcock, Edward, First anniversary address before the Association of American Geologists, this Journal, 41, 232–275, 1841.

[47]. Third annual meeting of the Association of American Geologists and Naturalists, this Journal, 43, 154, 1842; Abstract of proceedings of the fourth session of the Association of American Geologists and Naturalists, ibid., 45, 321, 1843.

[48]. Rogers, H. D., Address delivered before Association of American Geologists and Naturalists, this Journal, 47, 275, 1844.

[49]. Agassiz, Louis, The erratic phenomena about Lake Superior, this Journal, 10, 83–101, 1850.

[50]. Desor, E., On the drift of Lake Superior, this Journal, 13, 93–109, 1852; Post-Pliocene of the southern States, etc., 14, 49–59, 1852.

[51]. Dana, J. D., Manual of geology, 546, Philadelphia, 1863.

[52]. Dana, J. D., on the Quaternary, or post-Tertiary of the New Haven region, this Journal, 1, 1–5, 1871.

[53]. Matthew, G. F., Surface geology of New Brunswick, this Journal, 2, 371–372, 1871.

[54]. Maclaren, Charles, The glacial theory of Prof. Agassiz, this Journal, 42, 365, 1842.

[55]. Daly, R. A., Problems of the Pacific Islands, this Journal, 41, 153–186, 1916.

[56]. Catlin, George, Account of a journey to the Côteau des Prairies, this Journal, 38, 138–146, 1840.

[57]. Hilgard, E. W., Remarks on the drift of the western and southern States and its relation to the glacier and iceberg theories, this Journal, 42, 343–347, 1866.

[58]. Hall, C. E., Glacial phenomena along the Kittatinny or Blue Mountain, Pennsylvania, this Journal, 11, review, 233, 1876.

[59]. Stevens, R. P., On glaciers of the glacial era in Virginia, this Journal, 6, 371–373, 1873.

[60]. Rogers, W. B., On the gravel and cobble-stone deposits of Virginia and the Middle States, Proc. Boston Soc. Nat. Hist., 18, 1875; this Journal, 11, 60–61, 1876.

[61]. Kerr, W. C, Origin of some new points in the topography of North Carolina, this Journal, 21, 216–219, 1881.

[62]. Gilbert, G. K., On certain glacial and post-glacial phenomena of the Maumee valley, this Journal, 1, 339–345, 1871.

[63]. Chamberlin, T. C., On the geology of eastern Wisconsin, Geol. of Wisconsin, 2, 1877; this Journal, 15, 61, 406, 1878.

[64]. Chamberlin, T. C, Preliminary paper on the terminal moraine of the second glacial epoch, U. S. Geol. Survey, Third Ann. Rept., 291–402, 1883.

[65]. Wright, G. F., Unity of the glacial epoch, this Journal, 44, 351–373, 1892.

Upham, Warren, The diversity of the glacial drift along its boundary, ibid., 47, 358–365, 1894.

Wright, G. F., Theory of an interglacial submergence in England, ibid., 43, 1–8, 1892.

Chamberlin, T. C., Diversity of the glacial period, ibid., 45, 171–200, 1983

Dana, J. D., On New England and the upper Mississippi basin in the glacial period, ibid., 46, 327–330, 1893.

Wright, G. F., Continuity of the glacial period, ibid., 47, 161–187, 1894.

Chamberlin, T. C. and Leverett, F., Further studies of the drainage features of the upper Ohio basin, ibid., 47, 247–282, 1894.

[66]. Pumpelly, Raphael, Geological researches in China, Japan, and Mongolia, Smithsonian Contributions, No. 202, 1866.

[67]. Kingsmill, T. W., The probable origin of “loess” in North China and eastern Asia, Quart. Jour. Geol. Soc., 27, No. 108, 1871.

[68]. Pumpelly, Raphael, The relation of secular rock-disintegration to loess, glacial drift and rock basins, this Journal, 17, 135, 1879.

[69]. Binney, A., Some geologic features at Natchez on the Mississippi River, Proc. Boston Soc. Nat. Hist., 2, 126–130, 1848.

[70]. Hilgard, E. W., The loess of Mississippi Valley, and the eolian hypothesis, this Journal, 18, 106–112, 1879.

[71]. Chamberlin, T. C, Supplementary hypothesis respecting the origin of the loess of the Mississippi Valley, Jour. Geol., 5, 795–802, 1897.

[72]. Ramsay, A. C., On the glacial origin of certain lakes in Switzerland, the Black Forest, Great Britain, Sweden, North America, and elsewhere, Quart. Jour. Geol. Soc., 1862; this Journal, 35, 324–345, 1863. Preliminary statements of this theory appeared in 1859 and 1860.

[73]. Whittlesey, Charles, Smithsonian Contributions, No. 197, 1864.

[74]. LeConte, Joseph, On some of the ancient glaciers of the Sierras, this Journal, 5, 325–342, 1873, 10, 126–139, 1875.

[75]. King, Clarence, U. S. Geol. Expl. 40th Par., 1, 459–529, 1878.

[76]. Davis, W. M., Glacial erosion, Proc. Boston Soc. Nat. Hist., 22, 58, 1882.

[77]. Sabine, Sir Edward, Address of the president of the Royal Society, this Journal, 37, 108, 1864.

IV
A CENTURY OF GEOLOGY.—THE GROWTH OF KNOWLEDGE OF EARTH STRUCTURE

By JOSEPH BARRELL

Introduction
The Intellectual Viewpoint in 1818.

In 1818, the year of the founding of the Journal, the natural sciences were still in their infancy in Europe. Geology was still subordinate to mineralogy, was hardly recognized as a distinct science, and consisted in little more than a description of the character and distribution of minerals and rocks. America was remote from the Old World centers of learning. The energy of the young nation was absorbed in its own expansion, and but a few of those who by aptitude were fitted to increase scientific knowledge were even conscious of the existence of such a field of endeavor. Under these circumstances the educative field open to a journal of science in the United States was an almost virgin soil. Original contributions could most readily be based upon the natural history of the New World, and the founder of the Journal showed insight appreciative of the situation in stating in the “Plan of the Work” in the introduction to the first volume that “It will be a leading object to illustrate American Natural History, and especially our Mineralogy and Geology.”

At this time educated people were still satisfied that the whole knowledge of the origin and development of the earth so far as man could or should know it was embraced in the Book of Genesis. They were inclined to look with misgiving at attempts to directly interrogate the earth as to its history. Philosophers such as Descartes and Liebnitz, the cosmogonists de Maillet and Buffon had been less instrumental in developing science than in fitting a few facts and many speculations to their systems of philosophy. By the opening of the nineteenth century, however, men of learning were coming to appreciate that the way to advance science was to experiment and observe, to collect facts and discourage unfounded speculation. Silliman’s insight into the needs of geologic science is shown in the following quotation (1, pp. 6, 7, 1818):

“Our geology, also, presents a most interesting field of inquiry. A grand outline has recently been drawn by Mr. Maclure, with a masterly hand, and with a vast extent of personal observation and labour: but to fill up the detail, both observation and labour still more extensive are demanded; nor can the object be effected, till more good geologists are formed, and distributed over our extensive territory.

To account for the formation and changes of our globe, by excursions of the imagination, often splendid and imposing, but usually visionary, and almost always baseless, was, till within half a century, the business of geological speculations; but this research has now assumed a more sober character; the science of geology has been reared upon numerous and accurate observations of facts; and standing thus upon the basis of induction, it is entitled to a rank among those sciences which Lord Bacon’s Philosophy has contributed to create. Geological researches are now prosecuted by actually exploring the structure and arrangement of districts, countries, and continents. The obliquity of the strata of most rocks, causing their edges to project in many places above the surface; their exposure, in other instances on the sides or tops of hills and mountains; or, in consequence of the intersection of their strata, by roads, canals, and river-courses, or by the wearing of the ocean; or their direct perforation, by the shafts of mines; all these causes, and others, afford extensive means of reading the interior structure of the globe.

The outlines of American geology appear to be particularly grand, simple, and instructive; and a knowledge of the important facts, and general principles of this science, is of vast practical use, as regards the interests of agriculture, and the research for useful minerals. Geological and mineralogical descriptions, and maps of particular states and districts, are very much needed in the United States; and to excite a spirit to furnish them will form one leading object of this Journal.”

The Prolonged Influence of Outgrown Ideas.

Those interested in any branch of science should, as a matter of education, read the history of that special subject. A knowledge of the stages by which the present development has been attained is essential to give a proper perspective to the literature of each period. Much of the existing terminology is an inheritance from the first attempts at nomenclature, or may rest upon theories long discarded. Popular notions at variance with advanced teaching are often the forgotten inheritance of a past generation.

Gneiss, trap, and Old Red Sandstone are names which we owe to Werner. The “Tertiary period” and “drift” are relics of an early terminology. The geology of tourist circulars still speaks of canyons as made by “convulsions of nature.” Popular writers still attribute to geologists a belief in a molten earth covered by a thin crust. Within the present century the eighteenth century speculations of Werner and his predecessors, postulating a supposed capacity of water to seep through the crust into the interior of the earth, resulting in a hypothetical progressive desiccation of the surface, views long abandoned by most modern geologists, have been revived by an astronomer into a theory of “planetology.”

A review of the literature of a century brings to light certain tendencies in the growth of science. Each decade has witnessed a larger accumulation of observed facts and a fuller classification of these fundamental data, but the pendulum of interpretative theory swings away from the path of progress, now to one side, now to the other, testing out the proper direction. For decades the understanding of certain classes of facts may be actually retrogressive. A retrospect shows that certain minds, keen and unfettered by a prevailing theory, have in some directions been in advance of their generation. But the judgment of the times had not sufficient basis in knowledge for the separation and acceptance of their truer views from the contemporaneous tangle of false interpretations.

An interesting illustration of these statements regarding the slow settling of opinion may be cited in regard to the significance of the dip of the Triassic formations of the eastern United States. The strata of the Massachusetts-Connecticut basin possess a monoclinal easterly dip which averages about 20 degrees to the east. Those of the New Jersey-Pennsylvania-Virginia basin possess a similar dip to the northwest. Both basins are cut by great faults and the dip is now accepted by practically all geologists as due to rotation of the crust blocks away from a geanticlinal axis between the two basins. Edward Hitchcock, whose work from the first shows an interpretative quality in advance of his time, states in 1823 (6,74) regarding the dip of the Connecticut valley rocks:

“There is reason to believe that Mount Toby, the strata of which are almost horizontal, exhibits the original dip of these rocks, and that those cases in which they are more highly inclined are the result of some Plutonian convulsion. Such irregularity in the dip of coal fields is no uncommon occurrence.”

In Hitchcock’s Geology of Massachusetts, published in 1833, ten years later, geological structure sections of the Connecticut Valley rocks are given, the facts are discussed in detail and the dip ascribed to the elevatory forces. He says (l. c., pp. 213, 223):

“If it were possible to doubt that the new red sandstone formation was deposited from water, the surface of some of the layers of this shale would settle the question demonstrably. For it exhibits precisely those gentle undulations, which the loamy bottom of every river with a moderate current, presents. (No. 198.) But such a surface could never have been formed while the layers had that high inclination to the horizon, which many of them now present: so that we have here, also, decisive evidence that they have been elevated subsequently to their deposition....

The objection of a writer in the American Journal of Science, that such a height of waters as would deposit Mount Toby, must have produced a lake nearly to the upper part of New Hampshire, in the Connecticut Valley, and thus have caused the same sandstone to be produced higher up that valley than Northfield, loses its force, when it is recollected that this formation was deposited before its strata were elevated. For the elevating force undoubtedly changed the relative level of different parts of the country. In this case, the disturbing force must have acted beneath the primary rocks. And besides, we have good evidence which will be shown by and by, that our new red sandstone was formed beneath the ocean. We cannot then reason on this subject from present levels.”

Courtesy of Popular Science Monthly.

In 1840, H. D. Rogers, a geologist who has acquired a more widely known name than Hitchcock, but who in reality showed an inferior ability in interpretation, made the following statements in explanation of the regional monoclinal dip of the New Jersey Triassic rocks averaging 15 to 20 degrees to the northwest:[^[78]]

“Their materials give evidence of having been swept into this estuary, or great ancient river, from the south and southeast, by a current producing an almost universal dip of the beds towards the northwest, a feature clearly not caused by any uplifting agency, but assumed originally at the time of their deposition, in consequence of the setting of the current from the opposite or southeastern shore.”

In 1842, at the third annual meeting of the Association of American Geologists both H. D. and W. B. Rogers argued (43, 170, 1842) against Sir Charles Lyell and E. Hitchcock that the present dip of the Triassic was the original slope of deposition, stating among other reasons that the footprints impressed upon the sediments often showed a slipping and a pushing of the soft clay in the direction of the downhill slope. In 1858 H. D. Rogers still held to the same views of original dip,[^[79]] notwithstanding that a moderate amount of observation on the mud-cracked and rain-pitted layers would have supplied the proof that such must have dried as horizontal surfaces. The idea of inclined deposition is not yet wholly dead as it has been suggested more than once within the present generation as a means of escaping from the necessity of accepting the very great thicknesses of this and similar formations. Thus, as Brögger has remarked in another connection,—the ghosts of the old time stand ever ready to reappear.

In the present essay on the rise of structural geology as reflected through a century of publication in the Journal, attention will be given especially to two fields, that of structures connected with igneous rocks and that of structures connected with mountain making, and emphasis will be placed upon the growth of understanding rather than upon the accumulating knowledge of details. The growth in both of these divisions of structural geology is well illustrated in the volumes of the Journal.

Structures and Relationships of Igneous Rocks.

Opposed Interpretations of Plutonists and Neptunists.

During the first quarter of the nineteenth century the geologic controversy between the Plutonists and Neptunists was at its height; the Plutonists, following the Scotchman, Hutton, holding to the igneous origin of basalt and granite, the Neptunists, after their German master, Werner of Freiberg, maintaining that these rocks had been precipitated from a primitive universal ocean. The Plutonists, although time has shown them to have been correct in all essential particulars, were for a generation submerged under the propaganda carried forward by the disciples of Werner. The “Illustrations of the Huttonian Theory of the Earth,” a remarkable classic, worthy of being studied to-day as well as a century ago, was published in 1802 by John Playfair, professor of mathematics in the University of Edinburgh and a friend of Hutton, who had died five years previously. This volume was opposed by Robert Jameson, professor of natural philosophy in the same university, who had absorbed the ideas of the German school while at Freiberg and published in 1808 a volume on the “Elements of Geognosy,” in which the philosophy of Werner is followed throughout and even obsidian and pumice are argued to be aqueous precipitates. The authority of the Wernerian autocracy caused its nomenclature to be adopted in the new world, but strong evidence against its interpretations was to be found in the actual structural relations displayed by the igneous rocks.

Contributions on Volcanic and Intrusive Rocks.

The accumulation and study of facts constituted the best cure for an erroneous theory. The publications of the Journal contributed toward this end by articles along several lines. The most original contributions were those which dealt with the areal and structural geology of eastern North America, but equally valuable at that time for the broadening of scientific interest were the studies on the volcanic activities of the Hawaiian Islands, published through many years. Perhaps most valuable from the educative standpoint were the extensive republications in the Journal of the more important European researches, making them accessible to American readers. In volume 13 (1828), for example, a digest of Scrope’s work on volcanoes is given, covering forty pages; and of Daubeny on active and extinct volcanoes, running over seventy-five pages and extending into vol. 14. Through these comprehensive studies the nature of volcanic action became generally understood during the first half of the nineteenth century and the original publications in the Journal were valuable in giving a knowledge of the activities of the Hawaiian volcanoes.

Early in the nineteenth century the whole of America still remained to be explored by the geologist. The regions adjacent to the centers of learning were among the first to receive attention and the Triassic basin of Connecticut and Massachusetts yielded information in regard to the nature of igneous intrusion. This basin, of unmetamorphic shales and sandstones, is occupied by the Connecticut River except at its southern end. The Formation contains within it sills, dikes, and outflows of basaltic rocks which because of their superior resistance to erosion constitute prominent hills, in places bounded by cliffs.

Silliman in 1806[^[80]] described East Rock, New Haven, Connecticut, as a whinstone, trap, or basalt, and accounted for its presence on the supposition that it had

“actually been melted in the bowels of the earth and ejected among the superior strata by the force of subterraneous fire, but never erupted like lava, cooling under the pressure of the superincumbent strata and therefore compact or nonvesicular, its present form being due to erosion.”

In these conclusions Silliman was correct. With but a limited amount of experience he was able to discriminate between the intrusive and effusive rocks and saw that the prominence of this hill was due to the erosion of the sediments which once surrounded it.

An extensive paper on the geology of this region was published by Edward Hitchcock in 1823,[^[81]] then just thirty years of age. This paper shows the evidence of extensive field observations, and his comments in regard to the trap and granite are of interest. Hitchcock gives five pages to the subject of “Greenstone Dykes in Old Red Sandstone” (6, 56–60, 1823) and makes the following statements:

“Professor Silliman conducted me to an interesting locality of these in East-Haven. They occur on the main road from New-Haven to East-Haven, less than half a mile from Tomlinson’s bridge ... (p. 56).

They are an interesting feature in our geology, and deserve more attention; and it is peculiarly fortunate that they should be situated so near a geological school and the first mineral cabinet in our country ... (p. 58).