SCIENCE and INVENTIONS.

New Zealand Herald, Volume LVI, Issue 17234, 9 August 1919, Page 3 (Supplement)

SCIENCE and INVENTIONS.

WEALS PAT FOB MARGARINE. It is stated that in 1914 Denmark used 20,000 barrels of hardened whale fat 13 the margarine industry. Preparations are under way in Norway for utilising this material in the same way. The product is said to keep and taste well. Whale i it is even better suited for making lard. J-u this connection it is stated that exi periments are in progress in the United btates # with fish oils to determine the possibility of making them suitable for use in the human dietary. REMOVABLE COMBUSTION HEADS. Detachable heads for motor-car engines are now becoming standard by virtue of the immense difference which they make to the ease of removal of carbon deposit. On L-haded engines, where detachable heaas are used, there is a growing prac tice to abandon valve caps, and to remove the combustion head when it is dean eel to replace a valve. This may cause rather more work than the older valve cap system, but its adoption is usually followed by the introduction of the sparking plug direct into the water jacket, by which means the plug body is much better cooled. RADIUM! INDICATORS, Among the latest novelties in the electrical equipment field are the luminous pendants, buttons, and thumb tacks for indicating the position of a switch or | pull-chain socket in the dark. These peni dants, buttons, and thumb tacks are ! treated with a radium compound which i emits a steady glow in the dark, and which does not become exhausted for many years. Aside from serving to indi- j cate the location of electric switches and j pendants, these luminous indicators can be used for indicating the edge of a table, chair, piano, or other piece of furniture. WORLD'S ONLY AMBER MINES. The world's supply of amber is obtained from mines on the coast of Samland, in the Eastern Prussian peninsula, between the towns of Btirstrot and Palmnicken. These are the only amber mines known. Here countless ages ago, there were pine forests which the sea, through some convulsion of Nature, submerged. Then, by slow degrees, the wood was turned into stone, and the natural resin of the trees into precious "electron" of the ancients or the costly amber of the moderns, Tho shafts of the mine dip down far below the ocean bed. WATERPROOF PROPELLERS. A waterproof coating for airplanes propellers, which incorporates thin aluminium leaf in the finish, was developed by the Forest Products Laboratory at Madison, Wis., and placed in production by the War Department. The process is practically 100 per cent, effective in preventing absorption of water, particularly in the j storage stage. A French authority states that 80 per cent, of the French propellers ! nroduced are rejected by the pilots mainly j because they are out of balance. This difficulty is due largely to unequal absorption or distribution of moisture and can bo greatly reduced by an effective waterproofing coating. ' LISTENING 1 - TREES. It has been demonstrated that every j tree toy is a potential wireless tower. The discovery was made during army I manoeuvres at Camp Atascadero, California, I when it was found that telegraph and tele- ! phone buzzers, inoperative because of the dry season and unusual nature of the soil, became operative when connected with the trunk or roots of a tree. During hostilities the American Army, with a string of stations, using tree tops as antennas, read messages from ships at sea and the principal European radio stations, but, so far, transmission with the tree-top radio i has only been successful over short distances. ' MOTOR-CAR SIGNALLING DEVICE. There has recently been patented a signalling device which is intended to provide a means of indicating by day or night the direction in which a motor vehicle intends to travel. The signalling apparatus consists of two metal, arrows llin Jong, iitted at the front and rear of a ear. These arrows can be operatted simultaneiusly by means of two Bowden wires and a lever conveniently located on the dashboard or side of the body. The movements of the , arrow coincide with those of the hand lever. In conjunction with the handle, and electrically connected to it, is a means ' of operating an electric horn, so that when the arrow moves from one signalling position to another, the horn is sounded. The ! arrows are hollow and fitted with a glass : front, so that by means of an electric | bulb fitted inside, each can be illuminated. j ——— DNSiNKABLS SHIP. An unsinkable ship has been designed by a; shipbuilding expert, and will, it is chimed, result in future in the saving both of lives and of vessels. To make the ship unsinkable the bridge is being made hollow and airtight. It is to be fixed close (Sown 'o the deck, but with an attachment which vill permit of it being raised some distance. In the event of the ship being mined or holed in any other way so that she begins to sink, the bridge will be elevated to the full length of the attachment. It will float on the top of the water, and will also support the submerged hull until she can be taken to a place of safety, or at any rate until the craw have been nscued. The bridge will have accommodation for the crew where they would be protected from the inclemency of the weather. Shipowners who have 6een the designs consider the idea is an excellent one and quite feasible, and arrangements :,re being made to have a vessel built in I accordance with the design. j A PETROL-STEAM ENGINE. The latest trial of British invention is the Still engine, so named after its inenter, William Joseph Still. The Still engine, states the Autocar, is a machine . in which an explosion of gas drives the piston downwards, while steam generated j by the hot exhaust gases forces the piston | upwards. The use of steam and gas is not new, but a successful combination has not been obtained, hitherto. When the engine is working lh'ht but little steam is generated, the power being supplied by the exploded gas, but when at full load, or overload, much steam is generated, and this assists to function the piston. By means of the auxiliary boiler, the engine may run on steam alone, and the amount <_f "steam used can be controlled. The, mschine, therefore, is self-starting, can develop high power at low speed, and vary that power in accordance with its load. For small engines the power unit is somewhat heavy and certainly complicated, yet it possesses advantages greater than those of the ordinary petrol engine. HOISTING BY MAGNETS. The greatest attraction in the engineering world at present is a sort of glorified limpet, which, when lowered bv a crane, on to a girder, or rail, ingot, plate, piece of armour, or a heap of pig-iron or scrap, immediately sticks by magnetism and hoists the stuff ready for transportation to another place. The power is conveyed through a small cable, and the magnetic attraction is sufficient, in tie case of large magnet*about sft in diameter — pick up 40 tons. One of the most curious sights is to see a wooden packing-case clinging on to a magnet, the secret being, of course, tha£ the case contains nails or other iron or steel things. In view of tha extensive salvage operations which will engage the attention of the shipping world for a long time to como, it is interesting to note that these magnets can be lowered under the water and 6unk until they attach themselves to the iron or steel goods to be recovered- Another striking and useful feature of the magnets is that they may be used to handle hot pieces of steel such as : l ails or ingots, which men cannot approach to put hooks on. I