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

PETROL CARBURETTORS. 23 metal discs, either 011 the float or over the valve, as may be required. The ad vant age of a c ork float, when properly varnished and of good compressed material, is o its constant buoyancy, whereas a spun float has a tendency to leakage, although for the matter of that its replace- ment is easily and cheaply done. In the form shown in Fig. 21, the feed valve can be removed without taking out the float . Single Jet Carburettors.—-In order to work with a throttle-controlled mixture supply to the motor, it was quite early discovered that an induction feed carburettor would not supply a constant mixture at varying speeds unless either the fuel or the air supply was regulated ; in the earliest form of float-feed induction carburettor, patent ed by the writer in 1889, No. 9203, this purpose was achieved by varying the area of the divergent nozzle of a vena-contracta choke-tube, by a plug, p (vide Figs. 6 and 16), which was dravvn forward for a varying distance automatically, accorcling to the volume of mixture sup- plied, thus enabling the motor to be regulated by a hånd- or go vemor-cont rolled throttle, and over a considerable range of speeds,, without requiring any furt her adjustment to the fuel supply. In order that the highest possible air-stream velocity might be obtainecl in the choke-tube, n, with a minimum of throttling effect, it was found that a condivergent nozzle answered this purpose more effec- tively than any other form, that adopted being in accordance with the waist of a Vent uri water meter, and to further augment the inductive action of the air stream, and, to avoid any deflection of the fuel spray jet, this was drawn into an annulus surrounding the air nozzle, together with an auxiliary stream of air admitted through