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 sections of wooden plunger rod, and then releasing the cylinder from its base. Otherwise it must be pulled up with a pump puller and raised above ground until it can he dismantled. In any case the method of replacing is essentially as previously described for a simple aboveground pump.



Most plungers are constructed similar to the one shown in the photographs. To releather, clamp the spider carefully but firmly in a vise and then turn off the plunger end which threads onto the spider. The old leather can then be removed. If the retaining nut turns off hard, be especially careful in removing so as not to strain the spider to the cracking point. Turn it up a bit and then in the opposite direction until it will start. Sometimes a tap with a cold chisel in one of the notches will serve to start it. For general use a large pipe wrench is best suited for this job although there are special spanners that come with some makes of pumps for this purpose.

When disassembled, clean the threads on the spider and retaining nut and graphite them. Then slip the new cup leather in position, replace the nut and take up on it until the leather is held firmly in position, using care, of course, with this procedure. If a ready-cut cup leather cannot be procured, here is an excellent method of making one at home, using $1/8$-in. oak-tanned leather as material. Put the leather to soak in water for at least 24 hours while making the former, herein described.

Using an expansion bit, bore a hole in the center of a hardwood block 4 in. larger than the diameter of the plunger, and 1$1/2$ in. deep. Then fashion a round plug of hardwood just the diameter of the plunger and about 3 or 4 in. long. Thoroughly oil both pieces, provide some strong cord and have a large bench vise handy. When the leather is sufficiently pliable, place it over the hole in the block and then place the plug end upon it directly over the hole. Carefully turn the entire assembly on its side and place between the vise jaws. Then slowly turn up on the vise and push the plug into the hole, carrying the leather with it. Work very slowly so the leather will stretch over the plug during the process. When the bottom of the hole has been reached. leave the job alone until the leather has thoroughly dried out or, if the vise must 