SCIENCE NOTES.

Digger (Invercargill RSA), Issue 4, 9 April 1920, Page 15

SCIENCE NOTES.

FISHING BY TELEPHONE. Norwegian fishermen are adopting thcf telephone to warn them when great nuxnbei'o of fish are about. The submarine wa: has taught them the value of the telephone. A microphone, which in the ordinary way is called the mouthpiece, is lowered from a fishing boat and connected by a wire with the listening instrument in the boat. NEW WAY OF FINDENG OIL. A new method has been invented for locating oil, which saves the enormous expense of drilling in all sorts of likely places which may not eventually yield. The earth is a conductor of electricity, and a known electric current is passed through it from one spot to another in the region where oil is sought and is carefully measured, so that the resistance of the earth between the two spots is found. As oil-bearing deposits are bad conductors, the resistance will be great if oil is at hand, or small if not, and hy this difference, the presence of oil can be detscted. A SCIENTTEIC ROMANCE. Twenty-five centuries ago. Persian soldiers were armed with swords and spears made of a wonderful bronze, which could never be produced by the most skilled of modern metallurgists. A metallurgistnamed Samuel R. Dawson has now discovered the secret of the ancient bronze, which has been tested, and proves to be able to do just the things which the finest modern steels cannot do. The Pei'sian bronze, used at the battle of Marathon in 440 b.c., and now i*e-made, polishes with the lustre and colour of gold ; it does not corrode, it is harder than finest carbon tool-steel ; yet it can be drawn out to a wire of incredible thinness. Trolley wheek made of it have run 30,000 miles with little sign of wear. It is also being used for watch hair-springs ; being nonmagnetic and rnst-proof,- it, is an ideal substitute for steel. 300 WORDS A MINUTK As an indication of the rapid progress made in the transmission of wireless messages, an apparatus for sending 300 to 400 words a minute is to be mstailed at the naval radio station at Savville, U.S.A. Ihe present speed is ten wox*ds a minute. Ordinary convei'sation seldom exceeds 200 words a minute. Some eable-sending mac hines do 100. The apparatus cost about £10,000. An automatic sending machine, either of the disc or tape variety, ope«r-a-tes- a xnaster break key controlling thirty eight small lu'eak keys. In receiving niessa,gos, air vraves are photographed and from the developed films is printed a strip of paper with letiers forming the words indieated by the waves. An operator translates from the tape for tranacription of the message on a typewriter. The photographing and developing process takes twenty seconds..

SILK FROM SPIDERS. | Iji Madagasear, experimeuts have been made with spider's web as a substitute for silk, and the results are so encouraging that the opinion is that a great and luciative industry will result. Many persons have tried to utilise spider's web. in 1708, Bon Saint Hilaire, president of the Gourt of Accounts at Montpellier, a-e-tually made a few pairs of stoekings a,nd gloves of spider's web. In Madagasear, the spiders are boughi for about 8 cexits a-piece and put to work. About, four or five tirnes every ten davs they start t© spirt and continue until exhausted, Their product is wound on spools as fast as they spin it, and at each spinning 300 or 400 vards are obtained. The threads of a dozen spiders are twisted together, and two of these twisted strands are again twisted so t-hat a thread of twenty -four fir.ee threads is obtained. For fineness. strength, and beautiful yellow colour, this silk: is much superior to that of silk worms. TRAINS TO FIT ANY LINES. A French inventor has designed a novel arrangemmt of axle and suspension where by a railway carriage or truck may pass from a broad gauge to a narrow one or \[rc versa ; the axles and wheels suspen» si x i are so arranged that the distance between wheels automatically adjusts itself, in passing from one gauge to another, in such a way as always to fit the gauge of the rails. In its gimplest terms, the sohrtmn consists in extensihle axles. To go a little further into the means oi extenston, we find that the wheel suspension. is by special platforms, installed laterally be-i neath % central "chassis," which is attached to the under body of the can, Each axle is in reality formed of tvrt semi-axleg connected at the centre by a speeiai ai'rangement ©nablmg the system ie be telescoped by a distance which is lliiiited hy a eet of cormccfcxng rods.