Page:Popular Science Monthly Volume 9.djvu/136

118 atmospheric conditions. If we now transfer the instrument to a room in the house which has been closed for a few hours and without artificial heating, we find the internal conditions. If the dry thermometer is lowered, we may conclude that the walls are cold, and so absorb heat. If the difference between the wet and dry bulbs is lessened, we know the evaporation conditions are lessened; that is, that the internal atmosphere is overcharged with moisture. The two together will prove that the walls are damp, and that the house is disadvantageous to health.

New Tanning Process.—An exhibition was recently given at Havre, France, of Montoison's process of tanning. A variety of skins were experimented on, from the fresh skin of a calf, to the old skins of sheep and goats burnt and hardened by a tropical sun; more time of course was required to unhair the latter than the former. The skins were first soaked in hot water, then they received two coats of a pasty liquid on the inside, and were piled up, inside to inside, to undergo the action of the composition. After the skins had been soaked for a short time, the wool and hair came from them absolutely intact. The manner in which the wool came away from the skin by a touch of the hand created considerable astonishment in the minds of those who witnessed the experiments. In a few seconds the skins were dipped in two special baths to neutralize the unhairing composition, and the afternoon was devoted to tanning experiments, which proved the invention to be a complete success. Experienced tanners, who were present, declared the leather produced to be, to all appearance, fully equal to that produced by the tedious methods in common use.

The Economy of Vegetarianism.—A writer in the Quarterly Journal of Science makes a trenchant criticism of the arguments usually employed by vegetarians in support of their system of diet. The author considers the question from the economic, the moral, and the hygienic points of view, but we have not space to give more than an epitome of his remarks on the first of these topics. One hundred acres of good land, say the vegetarians, will support a greater amount of human life if planted with wheat, potatoes, or other crops directly consumed by man, than if laid out in pasture or set with vegetables intended for the food of cattle. This is true, but all land is not good; in every country there is abundance of land that is unfit for tillage, and which, nevertheless, yields excellent pasture. Under a vegetarian régime such lands would cease to supply the food-market. So too the produce of the forest and moor—game—would cease. More serious still, the waters would no longer contribute their share. It might be said that poor lands could still be used for pasture, and the produce of flocks and herds (wool, butter, cheese, milk) utilized. But if the grazer cannot sell the meat, it would be unprofitable to keep animals, unless he could get, for the products above named, prices a hundredfold higher than he gets now. Besides, the use of milk, butter, and cheese, is inconsistent with vegetarian principles. In a strictly vegetarian country, tallow, hides, and hair, could scarcely be procured. Again, the refuse of the fisheries is rising into importance as a manure fully equal to Peruvian guano. But, if fish might no longer be captured, the supply of this fertilizer would be cut off, unless indeed the destruction of animal life for purposes other than food received an exceptional sanction. Even then the cost of the raw material would be greatly enhanced.

Ancient American Civilization.—In the "Congress of Americanists," held last July at Nancy, France, a very learned paper was read by Prof. Foucaux, of the Collége de France, in favor of the theory that the ancient civilization of America is the work of Buddhist missionaries. The theory was hotly attacked by several of the distinguished men present, among them by Friedrich von Hellwald. The latter compared the story of Huei-shen to that of the sea-serpent. Dr. Hellwald is of the opinion that this theory received its death-blow at the Congress. Two other theories were also very badly damaged, namely, those of a lost continent of Atlantis and of Phœnician settlements in America. M. Léon de Rosny delivered a masterly address on the Maya hieroglyphics. The Maya was the sacred