The Vaporizing Of Paraffin for High-Speed Motors
(Electric Ignition Type)

32 VAPORIZING OF PARAFFIN. are used. The opening for the spray feed is a lateral sirt, the area of which is determined in an exact manner for different motors and running conditions, by the mitre-headed val ve l and index dial x ; the proportion of spray feed to volume of mixture admitted to the motor by the drum throttle n is determined by the vertical position of the tube b which is carried by the air regulator valve n ; the higlier the air valve is drawn up the wider is the area of the slots l, registering with the circular opening in the spray jet. The vertical position of the air regulator n and tube b, is shown as it would be, with the throttle drum lever pointing to, or nearly to, S, with the throttle almost closed, all the air then admitted having to flow between the neck of the regulator n and tube b, and will consequently acquire a high velocity, even with the motor running dead slow, or at starting. There is a two-folcl objection, however, to all carburettors having sliding air and fuel regulators : one, due to friction and wear, and applies more particularly to the spray valve, and the other, to liability to dust interference. Variable Pressure Flow Carburettors.—These belong to a type recently de vised in which the spray feed is regulated by difference of level in the nozzle, so that an automatically regulated constant mixture can be obtained without the aid of mixture-flow adjusted regulators, which are subject to wear, frictional resistance, and impurities in the air aspirated ; of this rather interesting type of carburettor, there are several modifications, some having one, otters two or even three spray nozzles, but for the purpose of this treatise, which has for its object the general trend of carburettor practice, and a description of the various methods that have been