EXHAUST NOZZLE.
The Exhaust Nozzle, as generally constructed, is an elbow attached to the end of the exhaust pipe in the smoke box or smoke stack of the boiler, the end of which points upward, with the opening reduced so that the exhaust steam will be forced up the stack, and thereby produce the same effect as a blower.
The opening in the exhaust nozzle should never be made so small as to check the exhaust steam to any great degree, and cause back pressure in the cylinder, as the power of the engine would be diminished. The opening should be as large as possible, and still produce sufficient draught to keep the required steam pressure.