Page:Popular Science Monthly Volume 53.djvu/154

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142
THE POPULAR SCIENCE MONTHLY.

us milk and wait to be milked, because the ancestral cow left her calf in hiding, and went far afield for pasture. Her chewing the cud depends upon her habit in early days of eating hastily when exposed to the attacks of wild beasts, and then digesting at leisure in her lair with comparative safety.

 

Abatement of Smoke.—The best method of abating the smoke nuisance has undergone a full discussion at the instance of the Franklin Institute, several meetings having been devoted to the subject, and communications having been invited and received from engineers and scientific men in different parts of the country, and the subject has been treated practically from a scientific point of view. The participants in the discussion seem all to have agreed that the abolition of smoke is practicable and not difficult; and most of them prescribe for the accomplishment of it the simple remedy of securing a perfect combustion of the fuel. This can be effected, according to Professor Thurston, of Cornell, and the others, through care and skill in stoking and by the use of properly constructed furnaces, without any costly apparatus. "Secure maximum temperature of furnace, producing the whole heat of combustion, as nearly as practicable, before commencing to take off heat for application to steam-making." This, according to Prof. L. M. Haupt, can be largely effected by intelligent firing, whereby a large amount of oxygen is admitted over the incandescent material instead of being forced through it. Experiences were related with patent devices, which with a bad fireman produced no better results than the plain fire box with a brick arch and a good fireman; and with the steam jet, which promoted quicker and more thorough mixture of the gases and air, and was good; but no device found better favor than the judicious, even distribution of the right proportion of added fuel over a hot fire. Finally, resolutions were adopted declaring the continuous and frequent emission of dense black smoke unnecessary, and advising that it be not permitted within the city limits. Accounts of special antismoke devices were avoided in this discussion, which related to general principles only; but inventors were given opportunity to describe and illustrate their apparatus at two subsequent meetings of the institute held in the fall of 1897.


MINOR PARAGRAPHS.

M. Moissan, who has had much success in preparing carbides of the metals by heating charcoal and the metals directly at the temperature of the electric furnace, now describes a new and general method of preparing these substances by placing together in the furnace a metallic oxide and carbide of calcium in fusion. The metallic oxide is reduced; the metal unites with the carbon, producing a crystalline carbide, and the oxygen combines with the calcium to form lime. By this method M. Moissan has obtained crystallized carbides of aluminum, manganese, tungsten, molybdenum, titanium, and chromium. In case the metal does not give a combination with carbon, it is obtained in free state as a melted button. There have been reduced in this way by carbide of calcium, to form free metals, the oxides of lead, bismuth, and tin. Silica is likewise easily reduced by carbon and gives carbide of silicon, or carborundum, a substance much used in industry.

President Gilman observes, in his semicentennial historical discourse at the Sheffield Scientific School, that the institution has been a department of a university "which never suffered its love of letters to blind its eyes to the value of science. In the days of closely restricted income, during the first half of the century, chemistry, mineralogy, geology, botany, mathematics, physics, meteorology, and astronomy were taught in Yale. Nor will any one think that scientific research was undervalued if be recalls the preparation of Dana's Mineralogy, the light that was thrown on meteoric showers, the studies of the aurora and of the zodiacal light, and the search for an intramercurial planet. Very different would have been the Sheffield record if it were not associated with the fame, the fortune, and the followers of a greater alma mater. . . . No conflict of studies has been heard of; no hostility between science and letters; no 'warfare' between science and religion. The Sheffield