Scientific.

Waikato Times, Volume XXVI, Issue 2119, 6 February 1886, Page 2 (Supplement)

Scientific.

Alloys of Copper and Cobalt.—The alloys which copper forms M'ith cobalt present a red colour and a fine fracture, which resembles that of pure copper. They possess a ductility, tenacity and mallability very remarkable, and lend themselves to forging, but do not take a temper. The alloys are obtained in a crucible with copper and cobalt, under a flux of boric acid and wood carbon. Several of such alloys were recently presentelbyM. Gmlleman to the French Academy of Sciences. They weie piepared by means of electrolytic red copper coining from the Noith German Refinery of Hamburg, and an alloy rich in cobalt, prepared by Mr Hussey Vivian, of Swansea. The composition of the alloy is, cobalt 48 28 per cent., nickel 1, copper r>o*26, iron 0 46. Pigs of this alloy, cooled in sand, and turned to a diameter of *79 inch, have been subjected to tractile force on a length of 7*87 inches. They were broken under varying charges of 15*8 to 22*8 tons per square inch, with an elongation of from 2S to 13 per cent. One alloy of 5 per cent, cobalt gave 21 6 tons on breaking, with an elongation of 15 per cent. The same alloy forged and of *79 inch diameter broke with 25*4 tons per square inch, after an elongation of 10 per cent. The price of the alloy is not great, owing to the comparative cheapness of cobalt. The alloy of 5 per cent, cobalt is particularly interesting for its useful qualities. It is inoxidizable and mallable as copper, tenacious and ductile as iron. M. Gtiilletnan proposes its uses for rivet 3, locomotive plates, tubes and so on. —Engineering.

DIhC'OVKHY OF THE FIRST MAH'ttOTU. — A Tuugoosian fisherman, named Schumacotf, about the }*ear 1799, was proceeding, as is the. custom of fishermen in those parts when fishing proves a failure, u!ong the shores of the Lena in quest of mammoth tusks, which have been there found" in considerable abundance. During his rambles, having gone further than he had done before, ho suddenly came face to face with a liuire mammoth embedded in clear ice. This extraordinary sight seems to have filled him with astonishment and awe; for instead of at once piofiting by the fortunate discovery, ho allowed several years to roll on before ho summoned courage to approach it closely, although it was his linbit to make stealthy journeys occasion-illy to the object of his wonder. At length, seeing, it is presumed, the terrific monster made no signs of eating him up, and that its tusks would bring him a considerable sum of money, he allowed the hope of gain to overcome his superstitious sciuples. He boldly broke the barrier of ice, chopped off the tusks, .and left the carcase to the mercy of the wolves and bears, who, finding ifc palatable, hoon reduced tho huge creature to a skeleton. Some two years afterwards a mm of science was on the ssent, and although so Lite in at the death, found a hujro skeleton with three legs, the eyes still in the orbits, and the brain uninjured in the ckull.—Cassell's Natural History.

A Cukr i*or Cobra Bites.—A remarkable cass of cure from the bite of a cobra in full poison comes from Pachmarhi, a military hill station in +.ho Central Provinces of India. The effective bite of a cobra is usually regarded as certain death, and the successful treatment of the case in question will suggest to medical men the possible value of hj'podermic treatment in hydrophobia and .such like cases. A post-office messenger was bitten by a cobra, which was afterwards killed. The man was at once taken to the Military Hospital, but ten or fifteen minutes must have elapsed before medical assistance was available. When tho patient was taken in hand ho was in a .state c,f collapse. The lower half of his body became gradually paralyzed, and by degrees he lost both speech and sight * The doctor, ,\t this atage, thought that nothing- could '•aye the man, especially as the dead snake had been examined and found to be .i cobra in full poi-on. Hyoodermic injections and other obvious treatment, however, we re continued, nnd in about ten hours some little improvement in the patient was ob-erved. Subsequently the man recoveied. There appears not the «li?htejit doubt about hi 9 having been fairly bitten, for, ii respective of the symptoms, his little finder had been torn open in shaking the snake off. The cobra was 4i feet long.

Magxesite Deposits. — A few years ago extraordinary deposits of magnesite were discovered in Syria. As is well known, no material is so admirably adapted for furnace lining, for durability aud fire-resisting properties as magnesite. The composition of the material is approximately as follows: Carbonaceous magnesia, 90*30 to 97*32 percent; carbonaceous limestone, o*os to 0-61 per cent; argillaceous earth, I*4o per cent; iron oxide, 4*49 per cent; insoluble residum, 3.73 per cent.. This residuum is found to consist of sillicio acid, 0*93 per cent; argillaceous earth, o*2l per cent* iron oxide, o*lB per cent; magnesia, 2#41 per cent. Magnesite, after being dead burnt, is chiefly employed in the form of magnesia stone for furnace bottoms, and already a considerable trade has sprung up for this and other purposes. The employment of magnesia stone, however, is not confined to the steel industry.

The Manufacture of Solid Carbonic Acid.—This has been carried on for some time by a company at Berlin. Bottles ef steel, containing eight kilos of liquid carbonic acid, are sold. From these, by allowing the liquid to escape into a cloud-verael, a quantity of solid acid is obtained which, by pressure into a wooden tube with a wooden piston, can be kept in the form of a small cylinder for a considerable time. A cylinder of about l\ inches diameter and 2 inches long will take five hours to melt away into gaf. The more it is compressed the longer it will last as solid.

The Solubility or Glass. —E, Bohlig, in a recent paper on the solubility of glass, described experiments which showed that 100 c. c. of distilled water, at the boiling temperature, will, in every two seconds, extract as much alkaline silicate out of glass commonly used, as will suffice to neutralize 01 c. c of solution containing 0.1 gram of oxalic acid per litre. With some old flasks and beakers no appreciable quantity was dissolved in the short time required for quantitative analysis. A Cheap Paint. — Ex-Commissioner Le Due gives, in the Husbandman, the formula for cheap paint for outbuildings and fences, to be made of sweet skim milk, mixed to thickness of cream with commen cistern cement (fresh) and applied to wood and brick. It is of a yellowish stone colour, and any pigment necessary to give it any desired colour can be added without injury to <fche paint. The lime of the cement and the casein of the milk form an insoluble compound,