Rensselaer Union, Volume 7, Number 34, Rensselaer, Jasper County, 13 May 1875 — MECHANICAL AND SCIENTIFIC. [ARTICLE]

MECHANICAL AND SCIENTIFIC.

—lt is said in an article by John C. Galton, on the song of fishes, -that fiftvtwo out of more than 3,000 species of fishes are known to produce sound, and that many of them emit musical sounds. —To cover cotton with silk Muller says that silk may be dissolved by hydrochloric acid, or ammoniacal solution of copper or nickle. The solution is filtered through sand, diluted until it begins to cloud, and the cotton, previously mordaunted, is then immersed in it for tw’o or three minutes, then removed and washed. The process is patented by the author. —Petroleum oils are coming into use for dressing leather, and it is stated that their use for this purpose is largely increasing. It is claimed that by the use of petroleum many advantages are gained, among which are: .that the leather can be reduced to a pliable condition more rapidly and with less cost than with pure animal oils; that the coloring of tanned leather is effected more rapidly and thoroughly than by the old process, and that the finished product is superior, both in pliability and toughness, to animal oils. The heavier gravities of petroleum, such as paraffine and steauirreduced oils; are the only ones used in this way. —Machine shop surgery is not the most delicate nor least painful, though men heroically undergo it rather than stand the loss of time due to an inflamed eye or festered finger. Iron filings have a way of imbedding themselves in the eye which defies almost every ordinary means for their extraction. For their removal, a small, blunt, pointed bar of steel, well magnetized, wifi be found excellent, and we should recommend that ' workmen liable to such injuries keep such an instrument about them. It would be a good plan to insert such a bar in a penknife, in a manner similar to a blade.— Scientific American. —ln place of using a special stone foreach color in the chromo-lithographic process, necessitating as many separate impressions as there are colors, the entire subject can be drawn upon a single stone, and a proof taken on a thin sheet of copper. This sheet is then cut out carefully according to the desired contour of the colors, and upon each of the portions is fixed a solid block of color, previously prepared. The whole is combined into one form, and is printed on an ordinary lithographic press, all the colors at once, the moisture of the sheet being sufficient to take off and hold the colors as the sheet goes through the press. —A series of experiments on innoculation with bee poison, made by Mr. G. Walker, is described in the department of “Nature and Science” of Scribner's Monthly. The method of procedure was to permit a bee to sting him on the wrist, care being taken to obtain the largest amount of poison. On the first day this operation was performed twice. The effect was a severe superficial erysipelas, with the ordinary symptoms of inflammation. After a few days these symptoms having disappeared, he caused the insect to sting him three times in quick succession. Though the erysipelatous inflammation was not so .-evere, a stinging s nsation extended up to the shoulder, and an enlargement of the lymphatic glands in the neck showed that the poison had been absorbed into the system. A few days afterward he again received three stings, which were attended by symptoms of less intensity. After the twentieth«sting there was only a slight itching sensation for a short time in the immediate vicinity of the wound, and the effects of the innoculation appeared to be perfectly satisfactory.