SCIENCE and INVENTIONS.

New Zealand Herald, Volume LV, Issue 13967, 28 September 1918, Page 3 (Supplement)

SCIENCE and INVENTIONS.

OALIFORNA'S BIG TREES. | The estimated age of mature big trees in California ranges from 500 to 2500 years, though soma may be several thousand years' old. The next oldest at maturity are the redwoods, but several pines range from 300 to 500.' The oldest big tree is thought to be about 7000 years from a seed. ACETYLENE GAS FOR ENGINES. It is reported that experiments are now being made in Norway to operate automobiles with acetyleno gas. No gasoline has been obtainable for many months, and practically no automobiles have been running. If the motors can be made to use acotylene gas, it can be manufactured in considerable volume from calcium carbide, which is produced in large quantities in Norway by means of waver power. The gis could be carried in cylinders under high pressure, or generated from carbide on the automobile itself. CONSERVATION OF AMMONIA. Nitrogerf 2xed in 'nearly any form has assumed unusual importance under war conditions. The conservation of ammonia, which is used in vast quantities for artificial refrigeration, becomes very necessary. The users of ammonia for this purpose are being urged to pay special attention to their insulation— of the gas escaping, and any other details of their equipment that can be improved—so that refrigeration may be carried on this year with less ammonia than ever before. DIAMONDS ISOM IRON. ' In the course of a lecture to the Institute of Metals Sir Charles Parsons explained the results ol the experiments from which he has propounded the theory of the production of diamonds from iron, and said that, while he was not disposed to speculate, he would suggest that it would seem probable that if a large mass of iron alloyed with other elements was submitted to suiitable heat treatment, and after setting, but when still permeable to gas, was subjected to carbon monoxide at a pressure of about 1000 atmospheres for a lbng time, segregations might take place slowly within the mass, and diamonds in Sayable quantity and size might be prouced. ANTI-SUBMARINE MINE FIELDS. • In speaking recently of the great mine fields in the North Sea, Sir Eric Geddes stated that these mine fir-Ids, which reach from Norway to the north coa.' of Scotland are gradually hemming in the enomy submarines. He drew attention to the barrage of. mine fields across the Straits of Dover and the mining operations which have been carried on in Heligoland Bight. The mines in the Bight have been laid by some of the fastest and finest craft of the British navy, which have gone into the Bight ct night to lay them. It is rarely that a ( German U-boat' attempts to break through the barrage at the Straits of Lower, which has proved to be highly efficient.

PAP 2'?. HORSESHOES.

A European inventor proposes to make a paper horseshoe that shall for general I purposes be the equel of the steel horseshoe in the following way:—Parchment paper is cut out in horseshoe form and built up to a suitable thickness by the use of a mixture of turpentine, Spanish white shellac, and linseed oil treated with litharge, and the whole is nlaced under the hydraulic press. This producer very light and uniform pieces, and it is *n easy matter to stamp out the nail hoies and grooves. Instead of nailing to the horse's hoof, they can be applied with an adhesive composition whose principal part is a solution of rubber in bisulfide of carbon. Paper paste could also be moulded into the shone | of a horseshoe by use of thepress, but the 1 result is - not as good as with the above. Among objections to it are these:—The surface is t too even and slipnery and the shoe would not hold well on the ground. AERONAUTICAL DEVICES WANTED. The Air Ministry wishes to make it known that the Air Inventions Committee, which was formed about nine months ago, has now received and examined upwards of 5000 inventions and suggestions relating to the air service, with whom any proposals of a practical nature which contain features of novelty, and may be of utility, are discussed. A subject which is intimately connected with the power-plant of aeroplanes is its noise. This constitutes one of the disadvantages of an aeroplane. For night flying a method by which it would be possible to hear from one aeroplane the approach of another would be of. great advantage. The engine can be silenced without serious disadvantages, but the noise of the propeller and the hum of the wires are so great that silencing the engine is not sufficient. Many hundreds of inventions and suggestions _ for inclinometers and instruments for straight flying and accurate bomb-dropping have been investigated. Efficient and welldesigned instruments for these purposes have, been available for some time past, but "it is quite possible that improved forms may be produced, though it is scarcely likely that this can be done by anyone who does not possess the necessary scientific and mechanical knowledge required for an investigation of this nature. Some inventors entirely disregard tho action of centrifugal force upon pendulum and spirit-level devices. DEPTH BOMB AND PATROL BOAT. The appearance of the depth bomb in U-boat warfare has enormously increased the offensive value of the patrol boat, says the Scientific American. Armed with this most efficient weapon, even the smaller converted craft, such as former steam yachts and motor boats, have become a terror to the U-boat when it is operating in the restricted waters towards which the ocean traffic converges in its approach to allied ports and harbours. This is true even of such craft as have only a moderate speed. For when a submarine submerges anywhere within range of the comparatively small guns carried by motor boat patrol vessels, there is an excellent opportunity for one or more of these craft to reach the point at which the eneifiy has disappeared, and drop its bombs before the U-boat is able to get beyond tho radius of destruction of their heavy explosive charge. Broadly speaking, the object of the patrol is to keep the submarine down, and the fact that even the smaller craft, to say nothing of the swift and powerful destroyers, are now carrying the depth bomb, has exerted a powerful moral effect upon Üboat commanders. The depth bombs are carried ready for instant use at the stern of the vessel on an inclined steel rack. Normally, the firing mechanism is restrained by a key, whioh is released whop the bombs are to be used. Also a graduated disc is provided, By the operation of which the bomb can be set to detonate at any predetermined depth. The firing is due to hydrostatio prosßure upon tho firing mechanism at the depth for which the latter is set. When a submarine has been seen to submerge, the patrol boat dashes for the spot and follows along in the direction tajfeen by the enemy and the accuracy &ith which the bomb Is detonated within destructive range of the submarine is determined by the judgement and skill of the patrol boat captain. In addition to the half dozen bombs 'in the rack there are two other depth bombs mounted on the rail and held in place by a cable provided with a catch, which, on being tripped, allows a bomb to roll off and drop into the sea. Below each of these and resting in ohocks on the deck are two more bombs, making ten in "all that are carried at the stern ready for use. The rack containing the half dozen bombs is inclined downwardly so that as each bomb is released it will roll toward the stern and drop, overboard.