[Illustration: Fig. 65.]

[Illustration: Fig. 66.]

_A_, steam pipe leading from the boiler. _B_, a perforated tube or
cylinder, through which the steam passes into the space _b_. _C_ screwed
rod for regulating the passage of steam through the annular conical space
_c_, and worked by the handle _d/_. _E_, suction pipe, leading from the
tank or hot well to small chamber _m_. _F_, annular conical opening or
discharge pipe, the size of which is regulated by the movement of the tube
or cylinder _B_. _G_, hand wheel for actuating the cylinder _B_. _H_,
opening, in connection with the atmosphere, intervening between discharge
pipe _F_ and the receiving pipe through which the water is forced. _I_,
tube through which the water passes to the boiler. _K_, valve for
preventing the return of the water from the boiler when the injector is not
working. _L_, waste or overflow pipe. _M_, nut to tighten the packing rings
_g_ and upper packing _i_ in cylinder _B_. _N_, lock nut to hold _M_.

The pipe _A_ is connected with the steam space of the boiler at its highest
part, to obtain as dry steam as possible. The passage of the steam into _A_
is controlled by a cock, as is also the feed pipe to the boiler. In
working, both are opened, the steam passes through _A_ into the space _b_,
and issuing through the nozzle _c_ with the pressure due to its head, and a
partial vacuum by its contact with the feed water, it drives this water in
connection with the jet through the pipe _F_ into the pipe _I_ in
connection with the water space of the boiler.

_Method of Working._--Turn the wheel so as to permit a small quantity of
water to flow to the instrument. Open the steam cock connecting the
apparatus with the boiler. Turn slightly the handle, which will admit a
small quantity of steam to the apparatus; a partial vacuum is thus
produced, causing the water to enter through the supply pipe. As soon as
this happens, which can be observed at the overflow pipe, the supply of
steam or water may be increased as required, up to the capacity of the
instrument, regulating either by means of the wheel and handle, so as to
prevent any overflow. The quantity of water delivered into the boiler, may
be varied by means of the stop cocks on the steam and water pipes, without
altering the handles on the injector; a graduated cock on the water supply
pipe is very convenient for this purpose.

The machines are manufactured by Wm. Sellers & Co. Philadelphia.

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