THE WORLD OF SCIENCE

Waikato Times, Volume 94, Issue 14776, 15 October 1921, Page 10 (Supplement)

THE WORLD OF SCIENCE

NEW ANAESTHETIC A coal-tar chemical for (he elimination of all pain in dental surgical operations, simple of application, and suitable for repeated and universal use in oral surgery, according lo the Sientitie American, is announced by Dr. Joseph A. Klein, of New York City. This new chemical is liquid in form, is applied on a pellet of cotton to Um gum or mucous membrane surrounding the tooth to me anaesthised, or into a cavity prior lo excavation where a tooth is to be filled or treated. It produces complete local anaesthesia in from two to eight minutes, and eliminates all feeling for from one to six hours.

Dr Klein has extracted teeth and pulps painlessly by the use ojf this chemical. Its effect is entirely local, so it may be applied with perfect safety, regardless of the patient's age cr general physical condition, and it is particularly valuable as an anaesthetic in the extraction of children's teeth. It leaves no disagreeable after-effect, but, because of its long period of activity, gives the nervous system ample time to recover from the shock or operation before the nerves in the area of operation regain their normal feeling or activity.

ELECTRICAL PROPULSION.

It is stated that the British Admiralty has decided to adopt electrical propulsion on several of the new battleships on its naval programme. With this equipment the turbines run at constant high speed I therefore at their highest efficiency), and drive electric generators which supply current through cables and control gear to electric motors which drive propellers direct at a low and —for propellers —most efficient speed. The advantages of electrical propulsion for ships, and especially for ships of war, were first painted out by British engineers, and the earliest patents in this branch of electrical engineering were British patents. It is probable that, in the course of time, every large ship in the world's navies will be electrically propelled, and that the system will extend to numerous liners and other vessels in the merchant service. Among the advantages of electrical propulslion are higher efficiency, absence of propeller "racing," greater space, economy in fuel, and increased care and efficiency of control. With electrical propulsion it is possible for the IMllcer on the bridge to navigate the ship simply by moving small electric switches. TAKES PHOTOGRAPHS IN THE DARKNESS. A few years ago the world was amazed at the extraordinary feat of exploding bombs at a distance of several miles, performed at Florence, Italy, by Professor Ulivi. But, unfortunately, Ulivi was proved to be faking, the exposure being made by Father Alfani the famous astronomer of the Pisa Observatory. Now, however, UlM'i has emerged from the retirement into which that disastrous experiment forced him to retire, and has again astounded men of science. His most recent feats are based, as the former were said to be, on the discovery of some rays of invisible light below the red of the spectrum, by means of which distant objects were made visible in the dark, and were even photographed. Professor Bobert W. Wood, of Johns Hopkins University, has a similar invention, called tne "chemical eye," but this is based upon the action of ultra-violet rays. UlHi, in discussing his invention with a Home correspondent, said that his was superior to that of Professor Wood because ultra-violet rays could not act at such great distances, were easily absorbed by the atmosphere, were reflected badly, and gave dim and shadowless images. Professor Ulivi says, too, that his •infra-red rays pass through fog and mist, as well as through water . His apparatus consists of a special search-' light covered with a plate prepared by himself, from which nothing passes except his infra-red rays. These rays arc projected on the enemy's fortifications, ships, and positions. The receiving apparatus consists of a photographic machine with a new objectglass and a special screen, on which the image of things struck by the rays forms itself visibly. Both objectglass and receiving-screen are the professor's own invention, and made entirely by himself, lie calls this discovery of his the "scotoscopia." . FACTS ABOUT COMETS. A comet has been known to get into a fearful shite of excitement, and end by throwing off its tail, bul never fails, iii that case, to get a new one. The tail is sometimes a hundred million miles long, but is made up of such light gasses that the mere pressure of light causes Ihem to he driven away from the direction of the sun. On two or three occasions the earth has passed through the tail of a large comet without suffering any ill-effects. Our globe, for example, went to a depth of 300,000 miles through the 1861 comet, and came out not a scrap the worse. Collisions with comets are more bogies, which should frighten no one. line very imaginative "philosopher" said that if a certain comet hit the earth we should have perpetual spring. Another individual -suggested Dial in the event of a collision the remains of the comet might be found to contain large quantities of gold and diamonds. Though several cornels have been known to have passed in front of the sun, there is no certain evidence that the head or any part, whatever has been projected against the sun's disc. If the head of a cornel is made up of stony or metallic fragments, these fragments must be not only of no great size, but, llicy must be a long way apart from one another. Due of the ancient philosophers taught that these bodies wcre no further off lhau our own atmosphere, but IJfiO years ago ;l great astronomer argued that Ihey were not only beyond the atmosphere, bul "much further off than the moon." This, of course, was far from the actual truth. The moon is about ■>■'), ooo miles distant, whilst millions of cornels go millions of miles farther away. The Anglo-Saxons, Creeks, and Unmans regarded comets as of Hie masculine gender. In those far-off days llicse bodies were known as "hairy stars." and il is probable ilia! their bearded appearance h'd lo the masculine description.

Speaking til Palmerston mi experiences in California, Mr .1. li. Merroll, Christchurrh. said, "farmers ami wlin are hoin.n' asked In ronliibulo lu arterial roads have im idea uf the groat savings in Lyrns ami petrol a highway means. Vim ran I ravel in California uver thousands of milo.a nn r<iail.s pcrfor.tly constructed, and llic ('armors and motorists who opposed the tax for their construction are now the £reatosl supporters of iurh roads, as they rut down the running expenses or motoring by oue-hAli.