Page:Popular Science Monthly Volume 22.djvu/738

720 of Columbus, Indiana, has suggested a new theory of the operation of solar and lunar gravities in producing the tides. The tide on the side of the earth nearest to the attracting bodies is induced by the acceleration of the rotation of the waters on that side causing them to rush up toward the point of greatest attraction. The tide on the opposite side is due to the formation of an axis of gravity by the combined attractions of the earth and moon, around the pole of which the water accumulates; in the same manner as if, when we had a fluid substance that a magnet would attract, and were to fill a vessel with it and hold a magnet under the vessel, we might expect the substance to accumulate to a greater depth immediately over the magnet than elsewhere.

Rev. James Challis, Plumian Professor of Astronomy, and Fellow of Trinity College, the senior of the professors at the University of Cambridge, died early in December, in the eightieth year of his age. He had actively discharged the duties of his professorship from 1836, when he was appointed to succeed Professor Airy, till within two years of his death. He published a considerable number of scientific works, including twelve volumes of astronomical observations.

"Moniteur Industriel" says that electrical force is regularly installed as the propelling power of the trains on the three railroads from Lichterfeld to Spandau, Prussia; from Port Bush to Busa Mills, Ireland; and from Zandvoort to Kostverloren, Holland. Electrical railway lines are in construction from Wiesbaden to Neroberg, Prussia; at Zankerode, in Saxony; a subterranean and subfluvial road in London; and one in South Wales, the motive power for which is derived from a fall of water. Of lines projected are the urban railways of the cities of Milan and Turin; the Edison Company's projected line in the United States; and the South Austrian Company's line.

is about to publish a work on the career of Galileo while he filled the chair of Mathematics in the University of Padua, from 1592 to 1610, a period of Galileo's life concerning which little has been hitherto published. It will contain about a hundred and fifty documents, for the most part unedited.

a venerable English diplomatist, a former vice-president of the Geological and Geographical Societies, and author of a work on the "Natural History of Buenos Ayres and the Rio de la Plata," died recently, in the eighty-sixth year of his age. He was also known to the scientific world for having taken to England the remains of the megatherium, glyptodon, and other great South American fossils.

death is announced of Andrea Aradas, of Catania, Sicily, a laborious student of marine zoölogy and paleontology, whose numerous publications extended over a period of forty years.

Peabody Museum of Archæology has acquired a collection of contemporary potteries in various stages of manufacture, and pottery-making tools, of the Caribs of British Guiana, which were bought in person several years ago by Professor H. A. Ward from a Carib woman whom he was watching make earthen vessels. Among the articles were several small and rude vessels which Professor Ward saw the Indian woman form and give to her children to play with and amuse themselves while she continued her work. These toy-vessels suggest that many of the small objects of similar character found in mounds and graves may have been the playthings of children.

formerly Professor of Astronomy and Director of the Observatory of the University of Upsala, Sweden, died November 21st, in his eighty-first year.

of the largest brains on record is that of an illiterate, not very intelligent mulatto, of Columbus, Ohio, who recently died at the age of forty-five years, and whose case is reported by Dr. Haldeman in the "Cincinnati Lancet." His brain weighed 68 ounces, or nearly five ounces more than the famous brain of Cuvier. The case was mentioned, in our December number, of a bricklayer who could neither read nor write, whose brain weighed 67 ounces.

death of the Marquis Orazio Antinori, the distinguished zoölogist and African traveler, is reported from Aden. He had just started, at seventy-one years of age, on a new expedition to the Upper Nile.

of the strongest evidences that practical education is destined hereafter to receive a fairer share of attention at the old universities is afforded by the fact that a course of lectures has been begun at Cambridge, under Professor Stuart, "On the Practice of Iron and Brass Founding, with Practical Demonstrations in the Foundry."

Director of the Observatory on Mount Vesuvius, announces that he has discovered, in the lava of that volcano, a spectrum line corresponding to that of helium, the element whose spectrum has hitherto been found only in the sun.

French Academy of Sciences presented M. J. B. Dumas, the chemist, on the 4th of December, a gold medal, in commemoration of his having reached the fiftieth year of his membership of the body. M. Jamin, representing the Academy, expressed wonder that it had only taken fifty years to do as much as M. Dumas had accomplished.