REVERSIBLE TURBINE.

Auckland Star, Volume XXXIX, Issue 203, 25 August 1908, Page 5

REVERSIBLE TURBINE.

INTERESTING AUCKLAND INVENTION. About forty gentlemen representing the principal engineering firms in Auckland, also including engineers of some of the steamers in port, assembled this morning at Beanev's Foundry, Arch Hill, for the purpose of witnessing a demonstration of a high speed, reversible turbine, the invention of an Aucklander, Mr John Marks. This engine has been made at the foundry of Mr Marks, and is a very compact piece of machinery. It was worked in the presence of the visitors, and, after going some time, the inventor turned some handles, and said with pardonable jpride: "Reversed, G'cntlemen," and so it undoubtedly was, the operation taking about three seconds to accomplish. It would therefore appear that this invention has at all events solved the important problem of reversible turbines, one -which has been the aim of many inventors ever since the turbine came into use. A feature about this engine is that it has no reciprocating or eccentric parts, all portions being perfectly round, and working from a dead centre. In order to do away as much as possible with vibration, the various working parts are truly balanced.- That the result aimed at has been achieved, is shown by the fact that the oil in the glasses affixed to the engine for lubricating the workings doee not dance. Friction on the working parts inside the casing is prevented by the formation of an equilibrium steam pressure, while each shaft is provided with adjustable collars for the purpose of preventing end motion, and these can be regulated to a very fine degree. Mr Marks explains that when compounded, the high pressure vanes will be free from back pressure, and the steam pressure will also be increased by the atmosphere. The rate at which the engine can be run may be estimated from the fact that the extended speed of the vanes is estimated to be 5280 feet per minute, with a boiler pressure of 170 lbs. per square inch. The engine was not, however, running at this speed, as the boiler pressure at the foundry is lOOlbs. Still Mr Marks claims to have come to that rate of speed proportionately with the pressure at his command. There are only two vanes on the engine, which is a great improvement, and Mr Marks

claims that his machine can be built at about one-third the cost -of an ordinary reciprocating one. In order to show the capabilities of the engine, it was connected with the shafting, and for a time ran all the machines in the foundry. This model, notwithstanding its small size, is capable of providing 30 hors* power. There is one point about the engine which, however, seems to require attention, that is the noise it makee, which would be a deterrent for use on steamers, and in many other places, bat this is probably one of those matters that can be remedied. TBe opinion of some of those present expressed was that the inventor had made an important discovery, and the engine was meet carefully watched by the experts. IV*bably the best recommendation it could have is that the workmen in the foundry have 'taken shares in the uyudfoate formed to exploit the invention.