CRANE. | Pumping Machinery. 311 
bearing the valve body descends, the valve passes downward 
through the water, the top, #, being raised, however, by the 
upward passage of the water. When the up stroke begins, 
the cessation of rising currents of water along with the weight 
of the water above the valve added to its own weight causes 
the top, H, to fall, thus closing the water passage. The water 
above the closed valve, not being able to escape through the 
valve, will penetrate any crack or opening which may present 
itself in the valve or between the valve and the working bar- 
rel; this is prevented by its entering the channels, H, and 
forcing the building out against the sides of the working bar- 
rel, thus making the valve practically water tight. 
The lower edge of the valve body, B, is cast with a circular 
chamfered edge, so that there will be less resistance to its 
downward passage through the water. 
Another form of working valve is shown in figure 83. It 
consists of a cast wheel, A, through which the pump rod or 
‘“snake’’ passes, and to which it is fastened. This wheel is 
slightly smaller than the inside diameter of the pipe or barrel, 
so that it will readily move in the same. A section of the 
wheel is shown at 6. A piece of rubber gasket or belting is 
cut to fit the top of the wheel, but is made somewhat larger, 
however, and is fastened to the top of the wheel by a lock 
nut, which aids in fastening the valve to the pump rod. A 
piece of three-quarter-inch square canvas building is tacked 
to the upper surface of the disk of gasket, and notched at two 
diametrically opposite points, as shown at L,in C and D. 
These notches are to allow the gasket to rise, as shown at O, 
in D, when the rod descends and the water rises through the 
valve. On the upstroke of the rod the gasket falls, as shown 
at Kin D, and as it is slightly larger in diameter than the 
inside of the pipe, it completely fills the pipe, as it rests upon 
the wheel below, and will raise the water caught above, al- 
lowing but little slip or leakage. This form of valve is cheap, 
simple, and easily repaired, but, due to the action of acid 
waters, it soon becomes loose on the stem or ‘‘snake,’’ and 
will bind in the working barrel and may break the stem, 
which is especially true when working with a quick stroke. 
