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288 of coal per horse-power. The Persia, built in 1856, had side-lever engines, indicating 3,600 horse power, and consumed 3 pounds of coal per horse-power. The Gallia, built in 1879, was fitted with compound engines of 5,000 horse-power, and sailed with a speed of 15 knots an hour. The Persia burned 6 tons of coal for every ton of cargo it carried; while the Gallia burned less than half a ton, although it carried the cargo 2 knots an hour faster than the Persia. The Arizona, with 6,000 horse-power, consumed 1 pound of coal per indicated horsepower, and carried 3,400 tons of cargo at an average speed of 16 knots, burning less than four hundred-weight per ton of cargo at a speed across the Atlantic faster than any previously recorded.

of Vermont, has made a series of examinations into the durability under heat of different kinds of granite, sandstone, limestone, marble, conglomerate, slate, soapstone, and artificial stone. Granite began to yield at a temperature of between 700° and 800°; it became cracked between 800° and 900°; generally cracked between 800° and 950°; and was made worthless by or before reaching a temperature of 1,000°. Sandstones showed a greater power of endurance, massive limestones still greater, and marbles the greatest, while conglomerates seem to have been among the weakest stones. The least absorbent and the most absorbent of the granites were equally the granites most destructible by heat.

annual meeting of the Society for the Promotion of Agricultural Science will be held at Cincinnati, August 16th, the day before the meeting of the American Association for the Advancement of Science. Papers will be presented by Professor W. J. Beal, on "Testing Seeds"; by Professor R. C. Kedzie, on "The Ripening of Wheat"; and other essays, the subjects of which have not been announced, will be read by Professor S. W, Johnson, Patrick Barry, Professors J. H. Comstock, E. W. Hilgard, and A. J. Cook, Messrs. J. J. Thomas, L. B. Arnold, and E. Lewis Sturtevant, M. D.

meeting of the French Association for the Advancement of Science at Algiers was successful in point of numbers, at least, notwithstanding the troubles with Tunis. A great many members had arrived on the 11th of April, fresh ones were coming in every boat, and it was thought that the attendance would exceed a thousand.

F. G. S., a well-known mineralogist, has recently died in London, at the age of seventy-three years. He was the possessor of one of the largest and most valuable collections of minerals, was for many years Professor of Geology and Mineralogy, afterward Professor of Mineralogy in King's College, London; he held the office of "Mineralogist to the Queen," and was consulted by the Government, as one of the best authorities on gems, with respect to the cutting of the Koh-i-noor diamond. He did useful work in preparing collections of minerals and fossils suitable for educational purposes and as a lecturer, and was author, in connection with the late Professor Ansted and the Rev. W. O. Mitchell, of the treatise on "Geology, Mineralogy, and Crystallography" in Orr's "Circle of the Sciences."

death is reported of Mr. F. A. Nobert, the celebrated producer of test-plates for miscroscopistsmicroscopists [sic]. He had been engaged for many years in ruling micrometers and diffraction plates, and produced one set of lines—his nineteenth band—equivalent to about 112,000 lines to the inch, which he believed could never be seen resolved in the microscope. Dr. Woodward eventually produced photographs of the finest of these lines; when Mr. Nobert ruled a new plate, the finest band of which—the twentieth—was of a fineness equivalent to about 224,000 lines to the inch.

New York Electrical Society was formed in this city on the 8th of February last, with the purpose of bringing persons engaged in operations connected with electricity into closer connection and association with each other for improvement in knowledge of electric art and science, and for social intercourse. The first regular meeting of the society was held on the 2d of March, when the organization was completed. Its real work was begun at the meeting of March 16th, when a paper was read by Mr. F. W. Gushing on the "Harmonic Telegraph" of Professor Elisha Gray. The preliminary meeting was participated in by between thirty and forty electricians and telegraphists: more than two hundred members had been enrolled at the meeting of March 16th.

Bart., M. P., one of the Vice-Presidents of the Geological Society, died in London, April 5th, in the seventy-fifth year of his age. He was chosen a Fellow of the Geological Society in 1829, and a Fellow of the Royal Society in 1831, and was also a Fellow of the Society of Antiquaries, antiquary to the Royal Academy, trustee of the British Museum, and one of the senate of London University. He was the author of fifty-one scientific papers, chiefly devoted to studies of fossil fishes, and generally published in the journal of the Geological Society, besides several papers in which he was joint author with other persons. He was owner of a collection of fossil fishes of remarkable value, it being but little inferior to that of the Earl of Enniskillen, which is, perhaps, the finest in the world.