Injector

—1. An apparatus by which a condenser or similar instrument may be temporarily inserted in an electric circuit. 2. A boiler feeding device, in which the momentum of a steam jet, directed by a series of suitably disposed conical nozzles, carries a stream of water into the boiler; the steam condensing within and heating the water which it forces along. The action of an injector is due to the fact that the velocity of a jet of steam flowing from a nozzle is much greater than water flowing under the same conditions. Although the injector has an almost perfect efficiency as a boiler feeder, it is not the most economical, since it can draw only moderately warm water, while a pump can feed water which has been heated by exhaust steathn which otherwise would be wasted.