191,140. Griffon, G. Oct. 4, 1921. Spray carburettors.-The fuel delivery is regulated by controlling the pressure above the fuel in the float chamber by a valve actuated by an elastically deformable casing the interior of which is subject to engine suction. A device of known form for running at low speed is also described. The float chamber receives petrol from a duct b, and is surmounted by and communicates with a partial-vacuum chamber j y which is open to the induction pipe through a duct k controlled by a manually-actuated cock k<1> and to the atmosphere through a manually controlled duct l and a duct w controlled by a valve n on the elastically deformable casing o. The interior of the casing communicates with the chamber i through a duct in the valve. With heavy suction, when the fuel flow would normally tend to be excessive, the casing o partly collapses and closes valve n thus increasing the vacuum above the fuel and diminishing its flow. The low-speed sprayer comprises a. duct e<1>, Fig. 4, in an adjustable tube e open to the atmosphere at e<2> and to an annular passage f<1> at c<3>. The annular passage communicates with the induction pipe near the edge of the throttle valve c<1> through ducts h, i. Petrol reaches the low-speed sprayer by a conduit a<2>. When the throttle is opened slightly, petrol which has filled the space f<1> is drawn into the induction pipe. If starting is difficult, the tube c is withdrawn from its seat by rotating the knurled head g.