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

WITH INDUCTION ATOMIZERS. 53 form of the one just described, tube ignition is or was used, and the ignition burner utilized to maintain a more regular temperature in the vaporizer than is possible by means of the exhaust alone. In this, known as Barker s, the space v is heated on the outside by the exhaust circulated through the jacket a;1, and on the inside is heated by the burner &. Paraffin is drawn up from the fuel supply tank along the pipe T:, this tank constitutes the base of the engine, and to compensate for difference of level (no feed cistern being used) the hollow screw- down feed valve P is adjusted slightly from time to time ; as in the vaporizers described in Figs. 37 and 39 to 41, a small proportion of heated air, about 8 to 10 per cent., is drawn down the centre of the feed valve from the belt a\ and assists in atomizing the spray. By the use of a lamp the vaporizer for engines having a cylinder diameter from 4 indies up to 10 or even 12 inches, can be kept at a sufficiently high temperature for the engine to be able to work with a clear exhaust on reduced loads for long periods, provided the burner keeps going properly, but is not strictly necessary when running at or nearly up to full load. The use of burners is carried another stage further in the Gardner high-speed electric ignition paraffin engines, referred to later {vide Fig. 84). Mention should also be made in this connection to an ■exhaust-heated paraffin vaporizer brought out by Smyers, as long ago as 1885, for use with the ordinary four-stroke gas engine, in which the feed was supplied by a pump, operated on the all or none principle. Suppressing Violence of the Explosive Action.—- In regard to the most suitable means for suppressing ex- cessive violence of the explosive action of heated paraffin