the Centennial Exhibition of 1876 are described in a volume of 600 quarto pages. Amongst his scientific investigations are remarkable computations of the influences tending to retard the earth's rotary motion, including the weight of material taken from below the earth's crest and piled above it by the hand of man. Ericsson was able to devote many years exclusively to the investigation of solar heat, and to the determination of the mechanical energy which the great luminary has in store for mankind when the coal fields become exhausted. A sun motor, illustrated in "Nature," vol. xxix., page 217, erected 1883, on his premises in Beach Street, was found to develop under ordinary sunshine a steady and reliable power, the striking features of this motor being that the part which receives the radiant heat, unlike the boiler of the steam-engine, does not deteriorate by the action of that heat-a trifling consideration, however, compared with the advantage that the inexhaustible solar storehouse supplies the fuel free of cost or transportation at every point within the temperate and tropical regions of our planet. The sun motor was the result of experiments conducted during twenty years. Its leading feature a rectangular trough, whose curved bottom, lined with polished plates, reflects the sun's rays toward a cylindrical heater placed longitudinally above the trough. This heater contains the steam or air employed to transfer the solar energy to the motor by cylinders provided with pistons and valves resembling those of ordinary engines. The operation of the sun motor in 1883 enabled Captain Ericsson to prove that the calculations made by certain French scientists, notably Pouillet, Vicaire, and Sainte-Claire Deville, assigning to the solar surface a comparatively low temperature, were incorrect, and that Newton's far higher estimate on the same subject must be accepted. Yet the cylindrical heater of the sun motor, constructed as it was solely for generating steam or expanding air, did not accurately determine the area acted upon by the reflected radiant heat. The rays, in the first place, acted only on part of the bottom of the heater, and their density also diminished gradually toward the sides, while imperfections in the surface of the plates prevented the exact course of the terminal rays from being defined. Accordingly the following year, 1884, Captain Ericsson erected a solar pyrometer of large dimensions. It was a polygonal reflector, composed of inclined mirrors, with a central conical heater, each point of whose surface received an equal amount of radiant heat in a given time. The mirrors were ninety-six in number, and the reflector and conical heater were sustained by a flat hub and eight radial spokes bent upward toward the ends at an angle of 45°. Another instrument of Captain Ericsson's was the pyrheliometer, designed to show the intensity of the sun's rays, and also his investigations of the surface and temperature of the moon. Seventeen years ago he announced before the American Academy of Science that the theory that the moon was devoid of water was a great error. He demonstrated that the great "ring mountains" cannot be composed of volcanic matter,"mineral substances originally in a state of fusion,"-but are inert glaciers made permanent as granite by perpetual intense cold. Pursuing this subject, Captain Ericsson has shown exactly how the annular glaciers are formed by vortex columns of vapor, and how the conical hills within the circular walls are formed. One of his conclusions was that the water on the moon bears the same proportion to its mass as the water of our oceans to the terrestrial mass, and that the aggregate water on the moon is 2,028,600 cubic miles. Captain Ericsson was proposed as one of the honorary members of this Society at its formation, but he declined to be so ranked, preferring to be considered as still among those bearing the burdens of active practice. His friends in this Society desired in 1886 to give him a testimonial banquet in recognition of his marvellous talent, but he would not hear of it, even when solicited by his most intimate friends. He was long intimate with both Messrs. C. H. Delamater and Thos. F. Rowland, who had been constructors of most of his successes. He died in New York on the 2d of March, 1889, and many members of the Society attended his funeral services as its delegated representatives. NOTE. This notice has been prepared in the main from facts which were collated by Colonel Pond and by Mr. Taylor, the latter Captain Ericsson's secretary for many years. CCCLVI. APPENDIX II. THE EUROPEAN TRIP OF THE JOINT PARTY OF ENGINEERS IN THE SUMMER OF 1889. It has been thought desirable that the transactions of the American Society of Mechanical Engineers, should contain a record of some of the features of the trip of its members to England, Paris, and Germany, during the summer of 1889.* Apart from the pleasurable side of the trip to those who participated in it, the nature of the entertainment received gave to the excursion almost an international significance beside what it possessed of professional profit. The account of it would naturally divide itself into I. Preliminaries. II. The Atlantic trip. III. Entertainment in England. IV. Entertainment in Paris. V. Entertainment in Germany. VI. The return and conclusion. VII. Addresses, and resolutions of thanks, and correspond ence. I. PRELIMINARIES. The first conception of a trip of a large party of engineers was doubtless that which lay, in 1880, and up to the time of his death, in the mind of the late Alexander L. Holley, Vice-President of the Society, and one of its founders. Mr. Holley labored hard to bring about such an interchange of courtesies, but for various reasons, at the time he tried it, his efforts were not successful. The first origin of the trip of 1889 was a suggestion at a dinner, given in London, by the President of the Institution of Mechanical Engineers of Great Britain, to two members of this Society. That preliminary conference led to the writing of the fol * There is also much of original and interesting matter of record on file in the office of the Society, where the initiative of many of the details has lain. lowing letter, which was read at the Nineteenth Meeting of the Society in Scranton, October, 1888: October 6th, 1888. THE PRESIDENT OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS. Dear Sir: I am authorized to invite your Society to hold a week's meeting in London next year, some time in May. We were given to understand that many of the leading American Engineers would visit Europe to see the Paris Exhibition of 1889. If your Society should accept the invitation it would be warmly welcomed by the Institution of Civil Engineers, the Iron and Steel Institute, and my own Society, viz., the Institution of Mechanical Engineers of England, and others. Your treasurer, Mr. Wiley, will more fully explain to you our desire to welcome our brother Engineers of America. I remain, dear sir, yours faithfully, Immediately, on the receipt of this letter, the Council appointed a committee of its members to ascertain the facts in reference to transportation, etc., for such a visit, and to ascertain from the members how many would be likely to participate. There was, therefore, issued in November, 1888, a circular, stating the facts in the possession of the Committee, and enclosing a postal card for reply. The Committee thought it desirable to divide the members into three classes: those who would certainly go, those who certainly could not go, and those who would be able to notify the Committee at a later date. This circular suggested that the minimum absence would be five weeks; that the cost per day per person would be $4 on shore,* and stated that the Committee had obtained from the Inman and International Steamship Company a round-trip rate of $110, and the tender of a steamer for our exclusive use, if we could fill its cabin. This circular was also sent in proof to the American Institute of Mining Engineers and the American Society of Civil Engineers. The former Society cast in their lot with the Mechanical Engineers at once, and, in everything which concerns the party, that Society was thereafter included. The first circular of inquiry from the Civil Engineers was not sent out until a later date. The favorable replies to this first circular, somewhat to the surprise of the Committee, showed a possibility of nearly three hundred persons taking part in the trip, and it was felt desirable that those who fully intended to go should be at once separated from those who merely hoped to go. * Experience showed that, in most cases, this should have been nearer $6 or $7. Accordingly, on January 15th, 1889, the second circular was issued to every one who had expressed himself as desiring to make one of the party, requesting him to remit the amount of the passage money for his party, with the understanding that the desirable accommodations on the steamer would be assigned in the order in which remittances were received. It seemed to the Committee that this was the only fair way to settle the delicate question of locating the members of the party, by having them stand in line, as it were, and thus claim their precedence. At the same time the Committee proceeded to protect themselves against the embarrassment which they feared when they had received favorable replies from more persons than the steamer could accommodate. They therefore procured from the Inman Line a further tender of privilege to berth a certain number on the fast steamer City of New York, of that line, at the increased rate charged for the same accommodations upon it ($125). This tender this Society did not make use of, to any large extent, but turned it over to the American Society of Civil Engineers (who were also in mind when the rate was asked for by the Committee) for the use of their members, and it was in this way that the party became divided into two groups. By February 20th remittances had been received from the members in sufficient numbers (132) to insure the securing of the proposed steamer for our exclusive use, and on that day the contract was signed by the representatives of the Society and the steamship Company, and the ship became ours.* Meanwhile the applications kept coming in, and the Company engaged to turn over also the after cabin of the steamer for the use of the party, and additional accommodation for thirty-four more persons was secured. The steamer City of Richmond was assigned to us, and our party on it numbered 166. Meanwhile, there had been received from the Institution of Civil Engineers, in London, the following communication: *The agents of the steamship line informed the Committee that, in the history of the Company's business, they were the first individuals to charter a vessel for exclusive use of their friends. |