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 be used for other purposes, tie block and plug together with the cord, as shown in drawing and set aside to dry.



When the leather is bone-dry, take off the cord, pull out the plug, and a nicely formed cup leather will be the result. Trim off the edges with a sharp knife, bevel the top edge on the inside, and then cut a round hole in the bottom to fit snugly around the retaining nut of the plunger.

With the new leather on the plunger, soak it in water again until softened and then insert in the pump cylinder and push down until the top of the rod can be again connected to the pump handle. It is also a good plan, with unlined cylinders, to wipe out the inside with very fine emery paper to remove any rust coating that may have formed through the years. This rough surface is particularly hard on leathers and wears them out before their time. Keep the cylinder walls clean and bright and the leathers will last much longer than would otherwise be the case.

The air domes on force pumps are usually provided with leather gaskets between them and the cylinder connection. When these grow hard they should be renewed. They can be cut from leather or sheet rubber, using the old one as a pattern, or marked out, as previously mentioned, with a ball-peen hammer. Leather gaskets are best, but for this purpose a thinner stock can be used than for the section leathers.

After the pump has been releathered and assembled a few days, it will be wise to go over all bolts and take up adjustments. New leather is flexible and it will probably be found that a turn or two can be taken up on all adjustments as the leather compresses. This will insure an air-tight job and give a positive vacuum in the cylinder. The plunger will, of course, have to be removed and the retaining nut turned up in the vise as before. If the cup leather has swollen too much and it works unduly hard, shave off a little from the edges with a safety-razor blade.

Now with the pump newly releathered, it should hold water indefinitely. If the water still persists in dropping back and the pump needs priming each time it is used, you may feel absolutely sure the leak is in the mechanical end of the affair. Go over all connections to see that they are drawn up tight. Inspect the castings and pipe sections above ground for cracks or leaky couplings. If possible, grab the pump base with a large pipe wrench and 