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 rudenesses of their own barbaric times." So Mr. Skidmore would find his substitute in diversion derived from pursuits, achievements, and habits of the children's elders. "In an age of mechanic arts and commerce, of which the great men are inventors, authors, business organizers, engineers, and self-made millionaires, with the eyes of youth trained upon them in admiration, interested in everything that pertains to their history, and eager to imitate them, it is nonsense to suppose that the boys can not be made to belong to such an age in their play as exactly as the men do in their work." The new play must call forth the constructive faculties, and manual training is held up as an element of it.

Propagation of Cholera.—The report of the Cholera Quarantine Board at Alexandria, Egypt, after reviewing the work of contending against the epidemic last season, inquires into the origin of the disease. According to information received in Egypt, the first cases of cholera were observed among the Yemen pilgrims immediately on their arrival at Mecca. It is known that cholera must have been prevailing in the Yemen as lately as the end of 1892. Discussions on the subject in the past have usually been very unsatisfactory and the conclusions very indefinite. The serious fact remains that cholera epidemics among the pilgrims annually collected at Mecca are of very frequent occurrence and are a standing menace to Egypt and Europe. Four times within the last twelve years the disease might have been introduced by the pilgrims into Egypt or Europe, or both, and the experience of France and Spain has shown how easily it might become endemic. The endeavors of the Quarantine Board have fortunately been successful in stamping out cholera before the pilgrims reached Europe.



for making coffins are exported in large numbers from Upper Tonkin to the province of Mongtze, in China. The trees from which they are made are not growing in the woods, but are deposited in what a French writer calls tree mines—that is, they are buried in a sandy soil at a depth of from seven to twenty-five feet, in good preservation, and some of them more than three feet in diameter. They probably once grew, judging from the character and position of the trunks, in a large forest which was buried by an earthquateearthquake [sic] or some other similar catastrophe. It is impossible to determine when the event took place, for no record of such a phenomenon is preserved; but the time can not have been extremely remote, for the upper limbs of many of the trees are still whole. The tree is a kind of pine, very pitchy, and therefore very durable; whence the demand for it.

vibrations of a building or a bridge may be registered by means of a bright gem which will reflect a ray of light upon a sensitive hand moved by clock work. It has recently been found by Dr. Steiner, of Hungary, that the vibrations of a stone bridge while a railroad train is passing over it at a speed of twenty-five miles an hour are much more extensive than had been supposed, and in the fact this author finds a new source of danger.

to a request of the Alpine Club, the Government of India has authorized its officers who are in a position to make them to institute observations of the movements of glaciers in the Himalayas.

quantity of evidence has been collected of a power in tobacco to destroy the micro-organism of cholera. Herr Wernicke wrapped cultures in cigars, inoculated them with sterile dry and moist unsterilized leaves, immersed them in infusions, and enveloped them in tobacco smoke; and in every case they disappeared in a few hours, except in a five-per-cent infusion, when they lived thirty-three days. Tarsinari found that they were usually killed after thirty minutes' exposure to tobacco fumes. Immunity from cholera has been observed among workmen in tobacco factories.

collected works of the chemist Jean Servais Stas are to be published as a mark of honor to his memory, under the direction of MM. Spring and Defaire, in three quarto volumes of about five hundred or six hundred pages each. The first volume will contain the memoirs and papers relating particularly to the determination of atomic weights; the second, notes, reports, and lectures; and the third, posthumous works, relating especially to spectroscopic researches.

concretions or "coal balls" found in the lower coal measures were the subject of a recent paper by H. B. Stocks in the Edinburgh Royal Society. They are remarkable for the perfect condition in which their fossil contents are preserved. Chemically they consist of carbonate of lime and iron pyrites in equal proportions. The perfect condition of the fossilized plant cells and fibers indicates that decay and petrifaction must have gone on simultaneously, and Mr. Stocks accounts for them by supposing that by the process of osmosis water containing 