10 SCIENCE OF SUCCESSFUL THRESHING. 



should be so attached that the pressure will be on the under 

 side of the valve seat. Then the packing around the valve 

 stem can leak only when the valve is open, and may be re- 

 newed at any time the valve is shut. A valve should not be 

 too tightly closed when cold as expansion due to heating 

 will force the valve so hard against its seat as to injure it. 



Starting the Fire. When the fittings are all in place, fill 

 the boiler with water, by means of the funnel, until the glass 

 gage shows about an inch and one-half of water. This is 

 on the assumption that the boiler is level and if not, allowance 

 should be made accordingly. The water will run in faster 

 if one of the gage-cocks, the blower or the whistle be 

 opened to allow the air to escape. The boiler being filled, 

 the funnel may be removed and the filler plug replaced. 

 When coal is used as fuel, wood should be used to start the 

 fire, the fire-box being kept full until steam begins to show 

 on the gage. Then, if it be desired to hasten the rise of 

 steam, the blower may be started and coal thrown onto the 

 fire. 



Oiling the Engine. While waiting for steam, the dope 

 may be removed from the bright work with rags or cotton 

 waste, saturated with benzine or kerosene. The oil holes 

 and cups are usually filled with grease at the factory to keep 

 out cinders and dirt during shipment of the engine. This 

 grease should be removed, so that the oil may reach the 

 place it is intended to lubricate. All the bearings should be 

 oiled, the oil cups being filled with good machine oil. Where 



