SCIENCE OF SUCCESSFUL THRESHING 



rocking-grates are arranged so that all ashes, cinders and 

 clinkers from a previous day's fire may be dumped into 

 the ash-pan and the grates entirely cleaned for a fresh 

 fire. However, while the engine is in operation, the lever 

 is ordinarily moved back and forth only enough to jar the 

 ashes through and not enough to dump the fire. Care 

 should be taken to leave the lever in such a position that the 

 grates form a flat surface, for otherwise the projecting 

 edges may be burned off. 



Exhaust Nozzles. It is always best to use the largest 

 nozzle that the fuel will allow. To be sure that you are 

 doing this, try a larger one if you have never done so. In 

 changing to another kind of fuel it is possible that the size 

 of exhaust nozzle may be increased. Frequently the firing 

 is made easier and burning of the fuel improved in every 

 way by the use of a larger nozzle. Often in burning coal, 

 the opening in the elbow is sufficiently small for the proper 

 draft, without using either of the reducing nozzles. The 

 reducing nozzles, being of brass, do not rust, and therefore 

 may be readily changed at any time. 



LIST OF EXHAUST NOZZLES FOR "CASE" ENGINES. 



