Louis Agassiz: His Life and Correspondence

by Louis Agassiz

. . .I hear that by some untoward circumstances, no doubt accidental, you have never received, my dear Agassiz, the letter expressing the pleasure which I share with all true lovers of science respecting your important undertaking, "Contributions to the Natural History of the United States." You must have been astonished at my silence, remembering, not only the affectionate relations we have held to each other ever since your first sojourn at Paris, but also the admiration I have never ceased to feel for the great and solid works which we owe to your sagacious mind and your incomparable intellectual energy. . .I approve especially the general conceptions which lie at the base of the plan you have traced. I admire the long series of physiological investigations, beginning with the embryology of the so-called simple and lower organisms and ascending by degrees to the more complicated. I admire that ever-renewed comparison of the types belonging to our planet, in its present condition, with those now found only in a fossil state, so abundant in the immense space lying between the shores opposite to northern Europe and northern Asia. The geographical distribution of organic forms in curves of equal density of occupation represents in great degree the inflexions of the isothermal lines. . .I am charged by the king, who knows the value of your older works, and who still feels for you the affectionate regard which he formerly expressed in person, to request that you will place his name at the head of your long list of subscribers. He wishes that an excursion across the Atlantic valley may one day bring you, who have so courageously braved Alpine summits, to the historic hill of Sans Souci. . .

Something of Agassiz's astonishment and pleasure at the encouragement given to his projected work is told in his letters. To his old friend Professor Valenciennes, in Paris, he writes: "I have just had an evidence of what one may do here in the interest of science. Some six months ago I formed a plan for the publication of my researches in America, and determined to carry it out with all possible care and beauty of finish. I estimated my materials at ten volumes, quarto, and having fixed the price at 60 francs (12 dollars) a volume, thought I might, perhaps, dispose of five hundred. I brought out my prospectus, and I have to-day seventeen hundred subscribers. What do you say to that for a work which is to cost six hundred francs a copy, and of which nothing has as yet appeared? Nor is the list closed yet, for every day I receive new subscriptions,—this very morning one from California! Where will not the love of science find its niche!". . .

In the same strain he says, at a little later date, to Sir Charles Lyell: "You will, no doubt, be pleased to learn that the first volume of my new work, 'Contributions to the Natural History of the United States,' which is to consist of ten volumes, quarto, is now printing, to come out this summer. I hope it will show that I have not been idle during ten years' silence. I am somewhat anxious about the reception of my first chapter, headed, 'Classification,' which contains anything but what zoologists would generally expect under that head. The subscription is marvelous. Conceive twenty-one hundred names before the appearance of the first pages of a work costing one hundred and twenty dollars! It places in my hands the means of doing henceforth for Natural History what I had never dreamed of before.". . .

This work, as originally planned, was never completed. It was cut short by ill-health and by the pressure of engagements arising from the rapid development of the great Museum, which finally became, as will be seen, the absorbing interest of his life. As it stands, the "Contributions to the Natural History of the United States" consists of four large quarto volumes. The first two are divided into three parts, namely: 1st. An Essay on Classification. 2nd. The North American Testudinata. 3rd. The Embryology of the Turtle,—the latter two being illustrated by thirty-four plates. The third and fourth volumes are devoted to the Radiata, and consist of five parts, namely: 1st. Acalephs in general. 2nd. Ctenophorae. 3rd. Discophorae. 4th. Hydroida. 5th. Homologies of the Radiates, —illustrated by forty-six plates.* (* The plates are of rare accuracy and beauty, and were chiefly drawn by A. Sonrel, though many of the microscopic drawings were made by Professor H.J. Clark, who was at that time Agassiz's private assistant. For details respecting Professor Clark's share in this work, and also concerning the aid of various kinds furnished to the author during its preparation, the reader is referred to the Preface of the volumes themselves.)

For originality of material, clearness of presentation, and beauty of illustration, these volumes have had their full recognition as models of scientific work. Their philosophy was, perhaps, too much out of harmony with the current theories of the day to be acceptable. In the "Essay on Classification" especially, Agassiz brought out with renewed earnestness his conviction that the animal world rests upon certain abstract conceptions, persistent and indestructible. He insists that while physical influences maintain, and within certain limits modify, organisms, they have never affected typical structure,—those characters, namely, upon which the great groups of the animal kingdom are united. From his point of view, therefore, what environment can do serves to emphasize what it cannot do. For the argument on which these conclusions are based we refer to the book itself. The discussion of this question occupies, however, only the first portion of the volume, two thirds of which are devoted to a general consideration of classification, and the ideas which it embodies, with a review of the modern systems of zoology.

The following letter was one of many in the same tone received from his European correspondents concerning this work.

FROM RICHARD OWEN.

December 9, 1857.

. . .I cannot permit a day to elapse without thanking you for the two volumes of your great work on American zoology, which, from your masterly and exhaustive style of treatment, becomes the most important contribution to the right progress of zoological science in all parts of the world where progress permits its cultivation. It is worthy of the author of the classical work on fossil fishes; and such works, like the Cyclopean structures of antiquity, are built to endure. I feel and I beg to express a fervent hope that you may be spared in health and vigor to see the completion of your great plan.

I have placed in Mr. Trubner's hands a set of the numbers (6) of my "History of British Fossil Reptiles," which have already appeared; a seventh will soon be out, and as they will be sent to you in succession I hope you will permit me to make a small and inadequate return for your liberality in the gift of your work by adding your name to the list of my subscribers. . .