Page:Popular Science Monthly Volume 13.djvu/784

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THE POPULAR SCIENCE MONTHLY.

The Coat of the Rocky Mount Sheep.—Western huntsmen who have chased the Rocky Mountain sheep, or big-horn (Ovis montana), generally believe that the animal wears only a coating of hair, never wool; but, in a communication to the American Naturalist, Dr. F. M. Endlich shows that this is an error, and that the big-horn varies in the nature of its covering according to the seasons, being clothed with hair in summer, and with wool in winter. On July 17, 1877, Dr. Endlich, while engaged in work connected with the survey of the Territories, found himself among the Wind River Mountains, at an elevation of 12,000 feet above sea-level, and amid large fields of snow. While contemplating the scenery around, he heard the sound of tramping feet, and, looking up, saw four mountain-sheep approaching, though at first he scarcely recognized the species. They were of a totally different color from any he had seen before, and seemed to have a very rough skin. Eight days later Dr. Endlich ascended a high peak in the same range, and, as he reached the timber-line, he saw a band of over a hundred big-horns. Some of these he shot and killed. The "hair" was shorter than usual. It was apparently growing rapidly, and pushing before it a layer of very fine wool, about half an inch in thickness. In other words, the sheep were shedding their wool, which is exceedingly fine, and of a light-gray color. Some portions of the body were already clear of it. This explained the peculiar color and appearance of the sheep seen a week previously.

 

New Method of annealing Glass.—A new method of annealing glass is proposed by Messrs. Albert and Weyer, of Paris. It consists in burying the articles to be annealed in powdered stone, plaster, lime, etc., or in grease, oil, melted nitrates of potash and soda, in short, in any liquid or solid capable of receiving the required heat, and remaining in a condition suitable for the process. By imbedding the articles in powder, they can be annealed at a very high temperature—a thing impossible unless some means are provided for supporting the objects and maintaining their shape when reduced to the softened state necessary to secure perfect annealing. By the new process the articles are filled with the powdered stone or other substance, and are then placed in crucibles and completely surrounded with the pulverized substance employed. They are then subjected to a heat gradually increasing to 200° Cent., or even 1,000° C. from four to six hours, and are then slowly cooled. When there is little danger of spoiling the shape of the articles, they can be annealed by the use of liquids and at less cost. In this case two boilers are employed, so placed that the liquid can be run from the upper into the lower. If nitrate of soda is employed, the temperature will be over 260° C. before the salt is melted, and the articles are then immersed in the cold state, and the temperature raised to 800° C. Then they are allowed to cool slowly, and when the temperature has fallen to nearly 260° C.—the solidification point—the nitrate is run off into the lower boiler, and a small fire is maintained beneath the upper boiler to prevent the too rapid cooling of the glass.

 

Influence of Chemical Research on Character.—Prof. Maxwell Simpson, President of Section B of the British Association, in his address makes some very judicious remarks on the influence of chemistry upon the intellectual habits and moral character of its cultivators. He first notes how the study of chemistry, or rather original chemical work, promotes accuracy, thoroughness, and circumspection. An organic analysis requires six weighings; if any one of these is inaccurate, the results are worthless. Unless the analyst is sure of every step in his research, his results are doubtful, and therefore of no value. Again, the original worker must be ever on his guard against error, and laboratory-work teaches us to use our senses aright, sharpens our powers of observation, and prevents us from reasoning rashly from appearances. Then, as regards the effect of original work on the character, in developing the virtues of courage, resolution, truthfulness, and patience: the chemist is often obliged to perform experiments which are attended with great danger, and no man can hope to fight long with the elements without carrying away many a scar. Sometimes fatal accidents occur. But the chemist must not be discouraged by fear of accident, neither must