Page:Popular Science Monthly Volume 36.djvu/445

Rh "artists' colors," Dr. A. P. Laurie said, in the British Association, that one point that came out in the course of his inquiries about the colors used by the old masters was the fact that they largely employed vegetable pigments, many of which were not used by modern painters. His researches into the ordinary methods of manufacturing colors showed that great variations prevailed in different makes of the same color, and the matter was an important one to look after. One of the most valuable oils used by the old masters was that of the walnut.

work of Columbus is to be commemorated in Italy according to a scheme adopted by a Royal Commission, which includes the publication of a "Raccolta Colombiana" in six volumes, devoted to (1) the writings of Columbus; (2) Columbus and his family; (3) the discovery of America; (4) navigation and cartography of the discovery; (5) monographs (Italian precursors and continuers of the work of Columbus); (6) bibliography. This work will apparently be the outcome of a large amount of diligent research.

establishment of a biological laboratory for the observation and study of freshwater Algæ was suggested by Mr. William R. Dudley, in a paper read at the meeting of the American Association.

has found, in experiments upon alum baking-powders, that most of the preparations of that class in the market are made with alum, the acid phosphate of calcium, bicarbonate of sodium, and starch. Among the resultants of the chemical changes by baking are aluminum hydroxide and phosphate. These substances, in doses not very greatly exceeding such quantities as may be derived from bread as commonly used, produce an inhibitory effect upon gastric digestion. This effect is probably due to precipitation in insoluble form of the organic substance constituting the peptic ferment and of some of the organic matter of food. Hence it is concluded that "not only alum itself, but the residues which its use in baking powder leaves in bread, can not be viewed as harmless, but must be ranked as objectionable."

to a calculation furnished us by Prof. William Harkness, of the Naval Observatory, "a body weighing one pound avoirdupois on a spring balance at the earth's equator would weigh only 0·16584 of a pound, or 2·6534 ounces, upon the same spring balance, at the moon's equator. In the statements on this subject appearing in books the centrifugal force is neglected. It amounts to 24 grains in an avoirdupois pound of 7,000 grains.

to a paper by Prof. Wiley, in the Society for promoting Agriculture, the butter of cows fed on cotton-seed is marked by the presence of a small supply of volatile acid and a high melting-point. The power possessed by cotton-seed oil of acting on silver, passes through the animal, and appears in the butter made from its milk—a fact which shows that substances can be carried directly from the food to the butter. A new standard of analysis will have to be adapted to the butters of cows fed on cotton-seed oil, for the low amount of volatile acid contained in them would cause them to be condemned as spurious.

relative values as foods of the grains named below are given by Prof. Wiley as, first, wheat; second, sorghum; third, maize; fourth, unhulled oats. Sorghum-seed furnishes a flour like buckwheat, that makes passable bread, and is coming into considerable use.

workmen in the Venetian glass factories at Murano, according to Dr. Salviati, fall victims in time to failure of eye-sight and ultimate blindness, caused by the excessive heat and intense glare of the furnaces. As they live simply and receive high wages, they are usually able to save enough before the disability comes upon them to support them for the remainder of their lives.

of Naples, has reported cures of tetanus by securing absolute rest for the patient—that is, rest for the senses as well as for the body. The patient's ears are closed with wax, his room is dark, and the floor is heavily carpeted. His nurse attends him with a shaded lantern; he is served food that requires no mastication; and sedatives are given to relieve pain. It is not pretended that this treatment shortens the period of the disease, but that it lessens the force of the paroxysms, which eventually cease.

by Dr. Pinel show that hypnotic patients will obey the directions conveyed to them mechanically by the phonograph as readily as they will obey living words. Hence, he argues, the theory of animal magnetism—that is, of a magnetic current passing from operator to subject—is baseless; and the real cause of the phenomena of hypnotism is a disordered mental state.

has endeavored to restore to the moon the credit that has been snatched from it of having influence over the weather and the welfare of men. Some of the superstitions relative to the moon may be traced to the old moon-worship. For others, Mr. Buckland assumes, ground may be found in fact. Meteorologists deny any influence of the moon upon weather; but the moon raises the tides of the ocean, and it also creates tides in the air, which have received no attention from science. We are ignorant of the forces that may reside in the air-tides and of the phenomena that may be dependent upon them.