BRITISH FORWARD MOVEMENTS.

Dunstan Times, Issue 3113, 17 April 1922, Page 8

BRITISH FORWARD MOVEMENTS.

The locomotive, now about a hundred years old, was a British invention, and to-day British engineers continue to introduce improvements in its design. Over forty years ago a deyicc known as the “exhaust steam injector” was brought out. Its purpose is to use the power in the exhaust steam from the cylinder to force water into the boiler. The first injector of this kind was able to do its work against a pressure in the boiler of 70 lbs per square inch. Later it was improved so as to feed at 120 lbs, and for higher pressures it was necessary to call in the aid of live steam from the boiler itself. Lately, however, a British firm invented a, modification by means of which the injector can work against a pressure of 150 lbs per square inch with one pound of exhaust pressure, thus effecting a great economy in live steam. This improvement is duo to the use of an additional nozzle which brings the steam into more effective contact with the stream of water. In practice the amount of live steam required when this new device is fitted is nearly half what it was formerly and amounts to only 2.j per cent, of the total steam produced by the boiler. The furnace may bo said to be almost the first industrial appliance ever produced, since it is in furnaces of some sort that metals are melted. And the beginning and the end of the art of tho furnace lies in controlling temperature. During recent years, especially since the development of electric furnaces, them has been remarkable progress in the accuracy of this control, and the summit appears to have been reached in an appliance recently displayed at a scientific exhibition in London, England. This instrument is intended not only to keep a furnace at a certain temperature but to raise or lower the temperature in accordance with any' pre-arranged programme. In general appearance it isi similar to a recording barometer, the pen tracing put a curve which vises and falls according to the temperature. A metal plate cut to a certain shape is laid over the chart, and if the temperature falls too low the pen conics into contact with the metal and completces an electrical circuit which operates mechanism arranged to raise the temperature of the furnace. Contrariwise. when the temperature gets too high the pen comes into contact with another part of tho metal actuating mechanism for reducing the temperature. The curves of tho metal thus determine the fluctuation in the furnace temperature. The design of engines for motor cycles present many problems of interest* to the engineer and of great importance to Life manufacturer. Simplicity. robustness, reliability, smoothness of running, efficiency, and many other qualities have to he combined in a machine which must in the end he cheap. Plainly because of this hist factor, many refinements employed in tho motor car engine, cannot be adopted in the motor cycle engine. Such conditions offer a clear stimulus to the skilful designer, and a new type of engine produced by a British firm marks a considerable advance towards the ideal. It is an air-cooled motor cycle engine with sleeve valves. Hitherto the use of the sleeve valve in any type of motor car engine has been looked at a little askance, owing to expected 1 rouble with lubrication and cooling. These troubles are not encountered in the numerous examples of automobiles fitted with sleeve valves; and their success has led this firm to adopt tho sleeve valve in an air-cooled engine—tho first time this combination has ever been attempted. One great advantage of the sleeve valve is its silent 'action; the public will be grateful for any reduction in the noise made hy motor cycles. The new engine has a single cylinder and gives a nominal output of I? horse power, hut it can, give a much higher power than this over long periods. As much as < horse power is produced at 7000 revolutions per minute. Its total weight is only 50 lbs. The number of parts in the engine is much less than in the ordinary type, and every detail is first class in material and workmanship. On many of the railway systems_ ol the world the phenomenon of “roaring rails’ ’ has been a too familiar trouble to engineers. The surface of the rails developed ridges at regular distances of an inch or so. and these corrugations led to excessive noise and vibrations. On electric tramway systems the same trouble appeared in even greater degree; frequently the noise was so excessive that the rails had to he ground flat at great expense —only la reveal fresh corrugations as soon as the traffic was resumed. All sorts ol explanations wen* oilered and lor a long time the precise cause of the trouble remained a mystery. Now the problem has been settled by a series of experiments carried out by a committee ol licitish experts on a tramway subway in Loudon, where the rails and track could he altered Ircely so as to test the various explanations put ionvard. ’I ho conclusion reached is that vibraI ion lias nothing to do with the case and that the real cause lies in the action of a very heavily loaded wheel running along the rail. This action makes the material of the rail surlace

“(low'’ into waves or corrugations very much as an ordinary road surlace Hows into waves under the action of a steam roller. The remedy therefore lies in the use of harder rails and. where possible. of larger wheels. (bitting and bundling wood for lighting fires j,s a process winch can be carried out on an economic basis only by very cheap labor or by very simple and efficient machinery. Cheap labor being a rare thing nowadays, there is an increased demand for machinery which will not only chop wood into the required lengths. _ but also arrange the pieces In suitable bundles. A new machine lor the latter process was recently constructed by a .British linn. The cut wood is fed on to an inclined shoot which delivers them to a conveyor b('ll running at a considerable spcc'd. It is thrown off the licit on to a slowly moving wheel with the partitions into which the pieces tall. Any piece which does not happen to fall into a partition drops hack again and is carried once more to the shoot. 'Jlic partitions deliver into a trough with an opening at the bottom. through which the pieces fall into boxes. As each box is filled, the operator presses a foot plate which removes the lull box and brings another into place for filling. The whole process is exceedingly rapid,, and the machine can be worked by one unskilled operator.