SCIENCE NOTES.

Otago Witness, Issue 2076, 7 December 1893, Page 48

SCIENCE NOTES.

— The claim has baen made by a Boston company of producing the first successful machine for electrical y forging round shapes. The machine, which ia designed and built for rapid and accurate work, is rotary in al! its movements, and thus no time or power is lost ia the return of the die 3 to their working position. Articles from up to Gin long &nd frcm to lin iv diameter can be turned out, the machine meeting, in its capability, the production of the great variety of things now made of iron or steel, of low carbon, in order that they may be turned out economically. By this machine, however, it appears that highly carbonised steel may be worked equally as well as iron or soft steel, and it is within its range to roll successfully steel of the highest grade of crucible down to the open hearth and Bessemer ; copper and brass are also satisfactorily worked. By this rollicg process 100 peifect handles are capable of being made in the time required to make one by former methods. Anti-friction steel balls, from -|in up to 2in in diameter, are likewise manufactured by this forging process at a speed otherwise unapproached. A red-hot steel bar is inserted between the revolving dies, and for every revolution of the dies a ball is forged, or a conical shot, a chair screw, a bolt with thread and head complete, a boiler rivet, a staple or taper pin, &c, are produced.

— The power of gradually adapting themselves to their surroundings possessed in such a remarkable degree by many microorganisms has been studied as regards their susceptibility to various strengths of disinfectants by Kossiakoff, and still more recently by Trambusti (Lo Sperimentale, 1892, fasc. i). Kossiakoff showed that a larger dose of a particular disinfectant was necessary to destroy an organism which had been trained by being subjected to gradually increasing doses of the disinfectant than was required when the organism was submitted to it without any such preparation. T«ambusti examined the behaviour of various bacteria in the presence of corrosive sublimate, and found that they exhibited striking differences in their ability to withstand this material. Thus whereas the pneumococcus of Friedlander was trained to survive an addition of 1 : 2000 parts of the sublimate to the culture media, the bacillus of fowl cholera was not able to withstand more than 1 : 30,000. If, however, the pneumococcus were taken straight from a fresh culture without any previous experience of the disinfectant, it succumbed in a solution containing 1 : 15,000 parts. The bacillus of swine plague (Eouget dcs pores) was inducel to resist an additioD of 1 : 8000 parts, whereas without training I: 15,000 parts infallibly destroyed it. As regards tie retention of their pathogenic properties amongst those organisms investigated, the bacillus of swine plsgue was the only instance in which the virulence was diminished during its treatment, an addition of 1 : 20,000 parts of corrosive sublimate reudericg it innocuous, although its vitality was not destroyed in the presence of 1 : SOOO parts.

— Professor Pickering, the American astronomer, who has been keeping Jupiter's satellites under close watch for same time at the elevated observatory maintained by Harvard on the Andes, in Peru, has found that they show marked changes of shapp, which taken in connection with the fact; that they have been proved to be very light, and all revolve ia the same direction, is held to make it very probable Lhat the satellites, instead of being solid bodie?, are rounded swarms of meteorites, which were onse spread out in the form of rings round Jupiter, as gaturn'd ring 3 are at present round Saturn. If this iaea can be demonstrated more completely it will form a very satisfactory bit of evidence as to the evolution of the solar system in general.

Turpin, the inventor of melinite, has submitted to the French War Office an electric gun alleged to be capable of discharging 25,000 projectiles in five minutes, and to have a range of several miles. The apparatus is comparatively light in weight, so that it can be drawn by two horses and worked by four men. The projectiles are small shelU charged with a secret chemical preparation, spreading death for 60yds around. The English Government is said to be negotiating for the purchase of. the invention, though soeptical of its value.

— Numerous experiments made in v hospitals and upon heroic scientists who have permitted tests to ,be made upon themselves right down to the moment oi death, warrant the following conclusions: — That a dying man may be burned with red hot irons and yet not feel the least pain ; that consciousness may remain in the dying almost to the moment of actual dissolution, but that most

people generally lose the power of thought long before death ; that in cases of death where there seems to be extreme suffering, with writbings and spasms, such phenomena are generally due to reflex muscular action ; also that fear weakens the muscular system and hastens death, while the reverse may prolong life. — French anthropologists agree that a few anatomical characters are not enough to determine a type of race, and that it is necessary to investigate all or as many as possible of such characters. Anthropology does not interfere with ethnology, because each has its distinctive field of inquiry. Anthropology does not say that physical characters are superior or inferior to linguistic characters ; it says that the two sciences^are of a different order and for a different purpose. The first relates to the physical element constituting peoples; the second to the classification of these peoples. Language grows, loses, borrows, changes, transforms, and all this independent of anthropological characters such as beliefs, customs, industries. Physical characters are hereditary and inherent in the blood, but linguistic characters are not. If a Red Indian is born among strangers and without the society of his parentg or race, he will speak not his own language but that of those who rear him ; but' he will retain all of the physical characters of bis race, notwithstanding. Different and opposing races may speak the same language, and on the | other hand the same race may speak different languages. — The soldering of glass and procelain with metals is a novel French process, and its adaptations are likely to be as numerous as they are valuable. It is also simple. The portion of the tube that is to be soldered i 3, according to an exchange, first covered with a thin layer of platinum, this deposit being obtained by covering the slightly-heated glass by means of a brush with very neutral chloride of platinum mixed with essential oil of* chamomile, the latter being slowly evaporated, and when the white and odoriferous vapours cease to be given off, the temperature is raised to a red heat ; the platinum is then reduced and covers the glass tube with a layer of bright metal. On connecting the tube thus metallised and placed in a bath ot: sulphate of copper to the negative pole of a battery of suitable euergy, there is deposited on the platinum a ring of copper which will be malleable and very adhesive if the operation has been properly performed. In this state the glass tube covered with copper can be treated like a genuine metallic tube, and be soldered to iron, copper, bronzi, platinum or any metals that can be united with the solder.