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

36 VAPORIZING OF PARAFFIN. turn fed by the nozzle s2; but as the nozzle s1 is larger than s2, the petrol level in the well l will be reduced by reason of an increased flow of mixture past the throttle on this being further opened ; thus, it will be seen in the section (Fig. 30), with throttle opening for half- speed, that the petrol level has fallen from Z1 to l-; also, with a still further opening of the throttle as shown in. the section (Fig. 29), the level has fallen to Z3, and as a consequence of this, the secondary nozzle s1 having to draw its supply from a variable level, will deliver a éorre- spondingly variable spray feed, in proportion as the volume of air drawn up the choke-tube b is varied, without the aid of any supplementary air valve or other com- pensating device, automatic action resulting entirely from differential functioning of a central jet drawn. from, a constant level and that of an annular jet drawn from a variable level. Multiple-Jet Carburettors.—In this class are in- cluded those in which multiple-spraying nozzles are suc- cessively brought into play according to the volunie of explosive mixture admitted to the motor, as distinguished from those in which the spraying capacity of one or more nozzles is influenced by a variable depression as in those just described, or by variable induction ; or again, a combination of both effects. The greater range and more constant degree of carburetion obtainable with the aid of multiple jets, is now beyond dispute, and is of the utmost value to motors in which flexibility for both power and speed is a factor of importance. What with the exigencies brought to bear by the intense national stress now in progress and the urgent demand for rapid transit, not only do the speed requirements