7O SCIENCE OF SUCCESSFUL THRESHING 



one side be coated with graphite when first put on, the 

 joint may be opened several times, and as the gasket will 

 adhere to one side only, it will remain undisturbed and will 

 not require renewing. In emergencies when no good 

 packing is at hand, a leaky joint can be remedied in vari- 

 ous ways. If small pieces of the packing blow out, the 

 leakages can be plugged temporarily by soft wooden 

 wedges. A gasket may be made of a piece of grain bag 

 smeared with paint or cylinder oil. Common straw- 

 board, or even a few thicknesses of newspaper, also an- 

 swers very well as a gasket under steam-chest cover, cyl- 

 inder-head or the like if the bolts be kept well tightened 

 for the first day or two. A soft copper wire about 1-8 

 inch in diameter will also answer the purpose, when placed 

 around the joint to be packed, inside of the bolts, and the 

 ends joined carefully. 



Packing Valve-Stems. For packing the stems of 

 globe and angle valves, the water-glass connections, throt- 

 tle-stem and similar places, asbestos wicking (which comes 

 in balls) is the most suitable. For valves that are not 

 subjected to steam-pressure and are therefore never heated, 

 cotton candle wicking or hemp will do nicely. 



The Crank-Pin and Disc. The crank-pin of an engine 

 will quickly heat if keyed up too tightly or if the grease- 

 cup which lubricates it is allowed to get empty. The 

 crank-pin is forced into the disc with a pressure of several 

 tons and will never get loose unless possibly by the pin 



