So the matter stood, until the centennial year, 1876, when Sir William Thomson paid a visit to this country. I passed a very pleasant evening with him at the Smithsonian Institution, engaged in a discussion, some points of which he afterwards mentioned in an address to the British Association. Among other matters, I mentioned this law, originating with Mr. J. Homer Lane. He did not think it could be well founded, and when I attempted to reproduce Mr. Lane's verbal demonstration, I found myself unable to do so. I told him I felt quite sure about the matter, and would write to him on the subject. When I again met Mr. Lane, I told him of my difficulty and asked him to repeat the demonstration. He did so at once, and I sent it off to Sir William. The latter immediately accepted the result, and published a paper on the subject, in which the theorem was made public for the first time.

It is very singular that a man of such acuteness never achieved anything else of significance. He was at my station on one occasion when a total eclipse of the sun was to be observed, and made a report on what he saw. At the same time he called my attention to a slight source of error with which photographs of the transit of Venus might be affected. The idea was a very ingenious one, and was published in due course.

Altogether, the picture of his life and death remains in my memory as a sad one, the brightest gleam being the fact that he was elected a member of the National Academy of Sciences, which must have been to him a very grateful recognition of his work on the part of his scientific associates. When he died, his funeral was attended only by a few of his fellow members of the academy. Altogether, I feel it eminently appropriate that his name should be perpetuated by the theorem of which I have spoken.

If the National Academy of Sciences has not proved as influential a body as such an academy should, it has still taken such a place in science, and rendered services of such importance to the government, that the circumstances connected with its origin are of permanent historic interest. As the writer was not a charter member, he cannot claim to have been "in at the birth," though he became, from time to time, a repository of desultory information on the subject. There is abundant internal and circumstantial evidence that Dr. B. A. Gould, although his name has, so far as I am aware, never been mentioned in this connection, was a leading spirit in the first organization. On the other hand, curiously enough, Professor Henry was not. I was quite satisfied that Bache took an active part, but Henry assured me that he could not believe this, because he was so intimate with Bache that, had the latter known anything of the matter, he would surely have consulted him. Some recent light is thrown on the subject by letters of Rear-Admiral Charles H. Davis, found in his "Life," as published by his son. Everything was carried on in the greatest secrecy, until the bill chartering the body was introduced by Senator Henry Wilson of Massachusetts. Fifty charter members were named, and this number was fixed as the permanent limit to the membership. The list did not include either George P. Bond, director of the Harvard Observatory, perhaps the foremost American astronomer of the time in charge of an observatory, nor Dr. John W. Draper. Yet the total membership in the section of astronomy and kindred sciences was very large. A story to which I give credence was that the original list, as handed to Senator Wilson, did not include the name of William B. Rogers, who was then founding the Institute of Technology. The senator made it a condition that room for Rogers should be found, and his wish was acceded to. It is of interest that the man thus added to the academy by a senator afterward became its President, and proved as able and popular a presiding officer as it ever had.

The governmental importance of the academy arose from the fact that its charter made it the scientific adviser of the government, by providing that it should "investigate, examine, experiment, and report upon any subject of science or art" whenever called upon by any department of the government. In this respect it was intended to perform the same valuable functions for the government that are expected of the national scientific academies or societies of foreign countries.

The academy was empowered to make its own constitution. That first adopted was sufficiently rigid and complex. Following the example of European bodies of the same sort, it was divided into two classes, one of mathematical and physical, the other of natural science. Each of these classes was divided into sections. A very elaborate system of procedure for the choice of new members was provided. Any member absent from four consecutive stated meetings of the academy had his name stricken from the roll unless he communicated a valid reason for his absence. Notwithstanding this requirement, the academy had no funds to defray the traveling expenses of members, nor did the government ever appropriate money for this purpose.

For seven years it became increasingly doubtful whether the organization would not be abandoned. Several of the most eminent members took no interest whatever in the academy,—did not attend the meetings, but did tender their resignations, which, however, were not accepted. This went on at such a rate that, in 1870, to avoid a threatened dissolution, a radical change was made in the constitution. Congress was asked to remove the restriction upon the number of members, which it promptly did. Classes and sections were entirely abandoned. The members formed but a single body. The method of election was simplified,—too much simplified, in fact.

The election of new members is, perhaps, the most difficult and delicate function of such an organization. It is one which cannot be performed to public satisfaction, nor without making many mistakes; and the avoidance of the latter is vastly more difficult when the members are so widely separated and have little opportunity to discuss in advance the merits of the men from whom a selection is to be made. An ideal selection cannot be made until after a man is dead, so that his work can be summed up; but I think it may fairly be said that, on the whole, the selections have been as good as could be expected under the conditions.

Notwithstanding the indifference of the government to the possible benefits that the academy might render it, it has—in addition to numerous reports on minor subjects—made two of capital importance to the public welfare. One of these was the planning of the United States Geological Survey, the other the organization of a forestry system for the United States.

During the years 1870-77, besides several temporary surveys or expeditions which had from time to time been conducted under the auspices of the government, there were growing up two permanent surveys of the territories. One of these was the Geographical Survey of territories west of the 100th meridian, under the Chief of Engineers of the Army; the other was the Geological Survey of the territories under the Interior Department, of which the chief was Professor F. V. Hayden.