With a piston pump you can pump water up from a depth of 5 meters. The supply line used to be in lead. The pump housing can be in wood, but is usually made ​​of cast iron. With frost, the pump must be protected or left blank. She easily breaks if it’s freezing. The seals are made of leather.

stenenpompThe pump is a cylinder, the bottom connected by a tube or hose with the soil- or well water, and from above, an overflow or outlet part. By pulling a properly fitting piston (leather closure) in the pump, the water is sucked up. The top of the partially cutaway piston is sealed with a (possibly weighted) leather disc. Which falls and squeezes closed (by the pressure of the water above) when the piston goes up. The water above the piston can escape through the overflow.
The piston is a rod with attached a large wooden disc with a leather strap on the closing edge.

When the piston goes down, the valve opens by the pressure of the water underneath.
There is a second valve or float needed in the top of the pump inlet hose. Usually this is a pointed, elongated small weight with on top a leather disc. It floats in the water upwards while sucking. When the piston goes down the leather remains sealing the hose, centered by a weight.

Air can still trough smaller chinks than water. Much closer the system, so much better it works. If there is air in, water may seep. The seals can dry out and distort, resulting in even more air coming in and water leaking out. Dry pumps will not work. The pump should be first cast with water, allowing it to work airtight again.

It works much better if there is a third (non-return) valve at the bottom of the tube mounted in the well. The valve can (as described in the second float) open in one direction (and let water pass). As a result, the water in the pump and the pipe cannot flow back. That avoids a lot of casting and useless dry pumping.

If you restore an old pump you can cut seals yourself from leather, or rubber from an old inner tube. First neatly and clearly draw them, because the material can deform and stretch during cutting. So work rather quiet and relaxed.