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864 of the Institute of Civil Engineers, contradicts the belief, which is general, that mine-explosions are always accompanied by a low barometer. Very few of the explosions of 1886 and 1887 were thus accompanied; and out of the list of disasters in the eleven years 1875-'85, given by Sir Frederick Abel, only 18·75 per cent of the accidents and 17·4 per cent of the deaths occurred when the mercury was at 29 inches or below. One half of this small percentage of explosions took place with a low but rapidly rising barometer, when gas had begun to issue from the strata.

has described his ideal of an anthropometric laboratory as a place where a person may have any of his various faculties measured, and where duplicates of his measurements may be preserved as private documents. Besides the ordinary simpler apparatus, such an institution should contain instruments for psycho-physical research, for determining the efficiency of each of the various senses and certain mental constants. Instruction might be afforded to those who wish to make measurements at home, together with information about instruments and the registration of results. A library would contain works relating to the respective influences of heredity and nurture. It might also fulfill a welcome purpose as a receptacle for biographies and family records.

having made certain measures of the thickness of a film of silver which can just be perceived by the eye, concludes that 0·0000002 of a millimetre is an upper limit of the diameter of a silver molecule.

said, in papers read in: the British Association on "Copper Wire," with particular reference to its use in telegraphy and telephony and high-speed telegraphy, that the speed of transmission on inland circuits had increased from eighty words per minute in 1870, to six hundred in 1887, and on the most difficult line to | Dublin, from fifty words in 1870 to four | hundred and sixty two in 1887. In fact, as many words could now be transmitted on one wire as on nine in 1870. Those improvements had been the results of greater perfection in apparatus, the elimination of electro-magnetic inertia, the improvement of the circuits (the wire and its surroundings), and the introduction of high-speed repeaters.

Jr., the distinguished conchologist, died at his home in Philadelphia, February 5th. He was conservator of the conchological collections of the Academy of Natural Sciences of Philadelphia, which is said to outrank even those of the British Museum, and was himself the owner of the most numerous collection in the world. He spent the later years of his life in arranging and systematizing the Academy's collection. He prepared the "Manual of Conchology, Structural and Systematic," which, although it has reached its fourteenth volume, is left unfinished. He was the author of a work on the marine conchology of the eastern United States and of a general manual of recent and fossil conchology, and was one of the founders and editor of the "American Journal of Conchology." His fame was world-wide, and his standing among conchologists in the highest rank.

Curator of the American Museum of Natural History, died suddenly at his home in this city, February 28th. He had been connected with the museum for several years, and had taken an important part in the arrangement and classification of its collections. He was a frequent writer on subjects connected with his lines of work, being the author of many articles in public journals, magazines, and scientific periodicals, and of books.

a French chemist, died in Paris, February 4th, in the seventy-fourth year of his age. After working in the laboratories of Orfila and Dumas, and in the Central and Municipal Schools, he established a manufactory of chemical products, at which subsequently Sainte-Claire Deville and Debray with his aid worked out the industrial fabrication of aluminum. He first applied pyrites to the fabrication of sulphuric acid, introduced a new preparation of charcoal, and devised the sugar process known as the Rousseau process.

death is announced of Dr. J. T. L. Boswell, a well-known English botanist, who was for many years Curator to the Botanical Society in London.

the eminent botanist of the University of Strasburg, died January 19th after a painful illness. He was born in 1831, was Professor of Botany successively at Freiburg, Halle, and Strasburg, was famous for his researches on the algae and fungi, was for many years after 1867 editor of the "Botanische Zeitung," and was the author of numerous treatises chiefly relating to cryptogamic vegetation, physiology, and morphology.

late keeper of the department of geology in the British Museum, died on the 21st of January, in the seventy-eighth year of his age.