Progress in Science.

New Zealand Graphic, Volume XLVII, Issue 20, 15 May 1912, Page 45

Progress in Science.

Wliy Steel in Cancrete Won’t Rast. IN these days of steel and concrete construction work, structural engineers are frequently asked what the fate of the buildings will be when the steel beams have rusted away. The best answer to that (says “Scientific Siftings”) is found in the report of the surveyor of St. Paul's Cathedral, who recently caused an opening to be made in the concrete of the dome in order that the condition of the great chain which binds it at its base mightbe disclosed. This chain has been imbedded in concrete for more than 200 years, and it was found to be as bright and perfect as when new. The reason why steel encased in concrete is prevented from rusting is. we are told, that the oxide of iron chemically combines with the cement, forming a covering of ferrite of calcium, which is a good protective agent.

Metal Cloth. An entirely new product, which takes up a position about midway between artificial silks and the fibres hitherto known which have been made from metal, has just been placed upon the German market oy a well-known Elberfeld firm. In contradistinction to the metal fibres so far known, Renar yarn does not consist of a metal core or main-thread spun round with tinsel; it is a core made of any suitable medium which, 'by means of a special process, is entirely covered with a metallic coating which becomes thoroughly incorporated with the core. At the same time all the metallic lustrous particles are so embedded in the external coat that they are protected against atmospheric or other extraneous influences, and thus maintain their sheen or lustre for an indefinite period. The yarn is not only

produced in the original colours of gold, silver, copper, old gold, etc., but is supplied ill any modern shade required; all these colours are characterised by a fine, striking .metallic lustre which will not fail to please, and which are reminiscent of silk and metallic lustrous combinations. The yarn can also'be worked up with artificial silk. From experiments made, it is fully proven that this new yarn is perfectly “fast,” that is to say it retains its colour aud never gets black or oxidised. Soldiers' Insensibility to Pain. It has long been known that a high degree of concentration of the attention in a certain direction produces a contraction of consciousness that may amount, to a genuine inhibition of pain stimuli arising from the periphery. Stories of soldiers wounded upon the battlefield who have not discovered their wounds until after the heat and the excitement of the battle was passed, are common enough in medical and popular literature. Essentially a psychic phenomenon, pain varies according to stoicism, familiarity of hardship, age, habits, and. above all, with the success won. In these modern days of anaesthetics we are hardly able to realise the heroism formerly required to place one's self beneath the surgeon’s knife. We can scarcely understand how, if the patient was able to survive the general shock of the operation, he could still survive the great pain that such an operation as a hip amputation would cause. Yet, according to some anecdotes related by Dr. Bonnette, a French Army surgeon, so patriotically exalted were many of the old veterans of Napoleon’s legions that they scarcely felt at all even the gravest operations. The legendary stoicism of the soldier of the Empire under the surgeon's knife (says the “Lancet Clynic”), may well be called to the attention of the young men of the army to-day, most of them so delicate,

so sensitive even to the prick of the viccinator needle; for man’s triumph over pain will always lie one of the most inspiring sights in the world.

An Armour-piercing Voice. With the aid of a 48dol. instrument known as the aerophone Grindell Matthews has just succeeded in projecting the sound of his voice through material which the biggest steel projectile on earth would fail to penetrate. I nited States Consul-General John L. Griffiths, of London, in a Consular report, says that Mr. Matthews was placed in the strong-room of a big London commercial house and locked in, with nine inches of armour steel, nine inches of fire brick, and six inches of concrete between him •and the outer world. By means of his small portable apparatus he carried on a conversation with an operator in another room on the farther side of the building. So distinct and faithful was Hie transmission that the experts in attendance were actually able to hear the tick of his watch, notwithstanding the almost inpenetrable mass between the two instruments. It is estimated that a complete set of instruments by means of which it will be possible to carry on a conversation through walls, mountains. or any other objects within a radius of five miles will cost about £9 12/.

Minerals in the Human Body. The human body contains, among other constituents, about two pounds of phosphorus, which is essential to the health of the bones and the vigour of the brain. This phosphorus, if extracted, and put to another use, would make up about 400 packages of friction matches. Besides phosphorus the body contains a few ounces of sodium and half an ounce of potassium. The quantity of the latter would be sufficient for many experiments in a class in chemistry. In addition to sodium and potassium, there are a few grains of magnesium, enough to make the “silver rain” for a family's stock of rockets- on a Fourth of July evening or to create a brilliant light visible at a considerable distance.

Edison's New Invention. Edison claims to have invented a storage battery for use in subnarine bails, which will enable crews to live beneath the water 1000 days. The largest per ventage of deaths in submarines is att ibuted to the ciew breathing exhaled carbonic acid gas, so Edison uses a potash solution in the new submarine battery, which, it is stated, will absorb carbonic acid gas, thereby purifying the atmo sphere. It will be necessary, of course, for submarines to supply themselves with fresh oxygen, but this may be accomplished, it is claimed, by carrying compressed oxygen in tubes. It is possible that Edison's , lainis may be substantiated, but one recalls similar claims made in the United Staes by other distinguished inventors which have completely failed to be realise I. The American Admiralty will investigate the new invention, which, if success, fill, will greatly improve, the conditions of submarine service.

4- ®> <?> Many Kinds of Flies, To the average householder, says the “Sydney Morning Herald.” there SS but two kinds of flies—the well-known but little respected “house" fly, and the more obtrusive, and consequently more fervently hated, “blow” fly. l f this were the true state of affairs in flydom it would be comparatively' fortnnate for humanity, but that is far from the reality. At a meeting of the Natur alists' Club one of the members exhibited a colleelion of flies captured in a suburban garden, hovering round some bunches of grapes. These included four independent and separate species o', “blow” fly, one flesh fly, one “bluebottle” and two varieties of “house” flies—one known as the typhoid fly, from its germcarrying habits. Also several other species of rarer fly that, however, are all more or less enemies to man. Among the collection were some common honey bees that had been caught in the act of cutting the grapes to obtain the sugar in them, and in this ease must lie counted enemies also.