PHILOSGPHICAL SOCIETY

Dominion, Volume 9, Issue 2797, 15 June 1916, Page 8

PHILOSGPHICAL SOCIETY

Mr. E. Parry, B.Sc., presided over a meeting of the Technological Section of I'hilosopliical Society last evening. AttGi tho exhibition of sodig interesting examples of corrosion in aluminium wire used for electrical purposes by the chairman, a .paper on the "Thomas System of .transmission" was read by Mr. 13. J Thomson, A.M.1.E.E., tho Now Zealand representative of the Thomas Company. Ho pointed out that tie oil engino as at present designed has a very limited range of economical speed, aiid hence for road purposes a transmission gear, with variable speed ratio, is a necessity. While the _tlireot mechanical drive is the most efficient known for any one speed, the change gear deuces, lie said, are untrustworthy and unmechanical above: low horse powers, and therefore the addition of a good. change speed device was looked for. This was obviously best obtained from an. electrical drive, and an ingenious combination of these two formed the Thomas system of transmission. One of the chief advantages of the system was the fact 1 that at half-speed and full-speed the drive was purely mechanical, and therefore highly efficient. Mr. Thomson showed a very fine set of slides picturing the rail motor car recently fitted up at Petone fortlie New Zealand railways, and now about to undergo exhaustive trials by tlie Eailway Department. The fact that both mechanical and electric drive are available at low speeds, and may be transmitted to difterent axles, mate this system particularly adapted for road train work. The needs of the Munition Department in England and France make these road trains particularly important just now, and a train was completed f6r, and tested satisfactorily, by the War Department last November, jn which the Thomas system of transmission was used, as well as a very ingenious drive and steering connection between the trailers, also designed by Mr. Thomas. A hearty vote of thanks to tho lecturer was passed..