gains the bank, evidently satisfied at his freedom from his tormentors. The solvent power of petroleum adapts it for use in the cleansing of steel articles. It does not become rancid or gummy, as is the case with other oils. The following patent has been recently granted for hardening steel. The object is heated to a red heat by any of the ordinary methods for uniform heating. It is then chilled by the action of a strong blast of air or gas. By suitable variations in the strength of the blast, and the temperature of the air, any required degree of hardness may be attained. After this the substance is tempered as is desired. In a discussion on the value of meat extracts as food, Max Von Pettenkofer holds that the extracts prepared, according to the present plan of Baron Liebeg, are quite equal to, if not superior, to meat itself. He thinks it bears the same relation to meat as cheese and butter bear to milk. The so-called vegetable wax of Japan and China is, in reality, the secretion of an insect about the size of a grain of rice. It receives its name because it is found on trees. After it is gathered, it is melted and strained; nearly 3,000,000 lbs. were exported from China in 1870. To avoid the errors which arise from weighing in the air, M. Deleuil, of Paris, has constructed a vacuum balance. It consists of a balance of the best description enclosed in an air-tight iron case, provided with glass windows, and suitable rods passing through stuffing-boxes. The vacuum is produced by an ordinary air-pump, and the weighings are very accurate. Putrid blood injected into the veins of a living animal is not mortal unless several drops are used; but the blood of an animal thus poisoned causes death in less than two days in such minute quantities as a trillionth of a drop. (N. Davaine.) The difference between the males and hermaphrodites of scapellum vulgare is so great, that when I first dissected the former, even the suspicion that they belonged to the class of cirripedes did not cross my mind. These males are half as large as the head of a pin; whereas the hermaphrodites are from an inch to an inch and a quarter in length. They consist of little more than a sack, containing the reproductive organs. There is no true mouth, or alimentary canal, but in place thereof there are rudimentary cirri around the opening of the sack, which appear to prevent the intrusion of enemies. (Charles Darwin.) Alexander S. Wilson states that the ash of diseased potatoes is deficient in lime compounds. The remedy is, therefore, self-evident. M. Monton relates a case of death by the administration of less than thirty grammes of nitrate of potash. Mr. Spencer placed a South African diamond, about the size of a pea, in the interior of a mass of refractory clay, which was mixed with soda and hydrate of lime. This was then kept at a cherryred heat for three days and nights, at the close of this time the diamond had disappeared, whereupon he concludes that carbon in this form is combustible at much lower temperatures than is generally supposed. By placing fresh orange flowers at once in boiling water, and collecting the distillate immediately, the product is superior to that obtained by immersing the flowers in cold water, and then raising the temperature. (M. Malenfaut.) Mr. John Galletely finds that cotton soaked in boiled linseed oil, and the temperature raised to 170° F., will then commence to generate heat, and in the course of an hour will acquire a temperature of 350° F., and shortly after that take fire. Raw linseed oil required about five hours, rape oil ten hours, olive oil six hours, lard oil four hours, seal oil about two hours, castor oil slight charring in two days, and sperm oil negative results. In toxicological examinations phosphorus may be separated from fatty matters by the solvent action of liquid ammonia or fats. From the residue the phosphorus is separated by the agency of ether. The solution thus obtained is purified by evaporation, and repeated washing with ammonia, the last traces of which are removed by water acidulated with sulphuric acid, and finally by distilled water. (Van Bastelear.) We are informed that the Signal Corps Station on Pike's Peak is 14,216 feet above sea-level instead of 11,000, as heretofore stated. Graeger finds that if commercial bone black is boiled in five times its weight of water, containing five per cent of carbonate of soda, and then treated repeatedly with muriatic acid, and then thoroughly washed and dried at 120° C., it is reduced to onefifth its original weight, but its decolorizing power is exceedingly intense. One litre of pure oxygen treated with electric discharges produces only seven millegrammes of ozone, while the same quantity of air gave thirty-seven millegrammes of ozone. (M. Boillot.) Osterlaud and Wagner find that the ashes and the lava of Vesuvius have the same composition, thus confirming the opinion that the ashes are merely pulverized lava. Duchemin thinks that magnetic needles should be circular instead of linear. The spectrum of chlorophyl is characterized especially by a red band, which retains a fixed position, even though the solution be diluted to 1-10,000which differs from other red bands in that it is divided into two portions by alkalies, and which always appears wherever chlorophyl exists, pure or adulterated. (J. Chautard.) |