SCIENCE OF THE DAY.

New Zealand Herald, Volume LXIV, Issue 19762, 8 October 1927, Page 5 (Supplement)

SCIENCE OF THE DAY.

LAND OF ETERNAL FIRES. Few regions are more remarkable than those near the Caspian' Sea. The waters of this sea once stretched far north and joined the Arctic Ocean, but now, after countless ages, they have receded to their present limits. Vast stretches of waste and barren land are left the waters once extended; deserts of reddish clay with occasional slimy marshes. This is the region known as the "Land of Everlasting Fire." For after sunset, leaping up on all sides from rents in the interminablo plain rise ghostly, daacing tongues of flame, untarnished by smoke, casting a lurid light all round. Dotted about lie squat, four-square temples, from whose pinnacles rise col-' umns of fierce flame, the dread gods incarnate of the fire worshippers. These columns are said to have burnt without intermission since the birth of Confucius. These everlasting fires are not the disembodied souls of dead men arid demons, as. the natn es believe, but are due to torrents of gas which stream out from underground regions and"are ignited spontaneously. In this amazing district it is possible to dig a small hole and then by applying n live coal to causo it to burst into flames. And if a tube of paper be stuck about two inches in the ground and the top of it touched with a live coal a flame will issue forth from it, while if the edges of the paper have been smeared with clay it will not catch fire. SOAP AS A HAIR BYE. Very early in Biblical history it was found that the ashes from fires, which were then always made of wood, were useful in removing grease from the hands. Ashes were thus the earliest form of soap, and remained so for a very long time. The first of the more civilised peoples to find out how to make real soap were the Romans. They learnt the secret from the Gauls, who used a preparation made from wood, ashes, and goat's tallow for washing their hair and beards, thus making them a fiery red—a colour they considered most becoming. The Romans developed their new discovery considerably, but it was many, many years before improved methods of soap-making were introduced. In some parts of the world soap-making is even now carried out in very much the same way as in Roman times. An old cask with holes bored in one end is filled with

alternate layers of straw, lime and wood ashes. The cask is then placed on a raised, slanting, grooved board, and from time to time water is poured on the contents, until a brownish liquid emerges, which is then collected in an iron pot and boiled over a fire with the fat or grease "until the soap-maker deems it finished. The fire is then allowed to go out, and the contents of the pot left to chill to a solid mass, after which it is cut up into bars. "YEAST" FOR CONCRETE. " Gassing" concrete to give it added lightness is a novel idea reported from Sweden. While the concrete, a mixture of sand, gravel, and cement, is still soft, gas is introduced into the mixture. This has the same effect on the concrete as yeast has on bread, filling it with small holes. The concrete produced is just as strong as the ordinary product, but much lighter. INCREASING RUBBER SUPPLY. Through the application of discoveries of Luther Burbank to the Dutch East Indian rubber plantations the output of the trees has been increased tenfold. The new process»is so successful, according to Mr. F. Henderson, president of the New York Rubber Exchange that further scientific researches into synthetic rubber would be commercially useless. Through the grafting of buds it has been found that a single tree, which ordinarily produces only 31b. or 41b. of crude rubber in a year, may be made to produce 701b. Yields" from bud-grafted areas have run from 8001b. to 50001b. an acre, while under present conditions the average yield is 3201b. As a result of experiments, Mr. Henderson says he believes it should be quite possible for rubber to become cheap enough to cause a great extension of its use without curtailing the profit to the grower. The lower price is likely to put an end to the reclamation of used rubber, a process by which the United States obtaics 34 per cent, of its rubber.

SOLUTION TO PUZZLE HO. 24