SPARK ARRESTER.
Traction engines are supplied as a usual thing with spark arresters if they burn wood or straw. Coal sparks are heavy and have little life, and with some engines no spark arrester is needed. But there is great danger of setting a fire if an engine is run with wood or straw without the spark arrester.
DIAMOND SPARK ARRESTER.
Spark arresters are of different types. The most usual form is a large screen dome placed over the top of the stack. This screen must be kept well cleaned by brushing, or the draft of the engine will be impaired by it.
In another form of spark arrester, the smoke is made to pass through water, which effectually kills every possible spark.
The Diamond Spark Arrester does not interfere with the draft and is so constructed that all sparks are carried by a counter current through a tube into a pail where water is kept. The inverted cone, as shown in cut, is made of steel wire cloth, which permits smoke and gas to escape, but no sparks. There is no possible chance to set fire to anything by sparks. It is adapted to any steam engine that exhausts into the smoke stack.
1 Unless otherwise indicated, cuts of fittings show those manufactured by the Lunkenheimer Co., Cincinnati, Ohio. [return]
2 This kind of safety valve is now being entirely discarded as much more dangerous than the spring or pop valve. [return]
[CHAPTER III.]
THE SIMPLE ENGINE.
The engine is the part of a power plant which converts steam pressure into power in such form that it can do work. Properly speaking, the engine has nothing to do with generating steam. That is done exclusively in the boiler, which has already been described.
VIEW OF SIMPLE CYLINDER.
(J. I. Case Threshing Machine Co.)
The steam engine was invented by James Watt, in England, between 1765 and 1790, and he understood all the essential parts of the engine as now built. It was improved, however, by Seguin, Ericsson, Stephenson, Fulton, and many others.
Let us first consider: