CALIFORNIA PUMP.

A very useful pump, in regions where transportation is a problem, is the California pump. It is a rough chain-pump. A box 10 inches by 3 inches, inside measurement, and 10 feet to 30 feet in length, according to requirements, forms a tube reaching from the water to be removed to the level at which it is to be discharged. In this an endless band of stout canvas or leather works, passing under a roller at the lower end, which is immersed in the water. At the higher end the belt passes around a drum worked by water, horse, or manual power. On the belt are wooden or metal projections that fit the box, forcing the water upward as the drum revolves.

HYDRAULIC DATA.

The prospector, and more especially the miner, will do well to commit the following figures to memory:

A head of 10 feet gives a pressure of about 41/3 pounds to the square inch. Let H represent the head of water in feet, and P the pressure to the square inch. Then:

H equals P times 2.311.
P equals H times .4326.

A FIRE LUTE.

To make a fire-proof joint between the lid and body of a retort, or crucible, use the following as a lute:

Quartz sand.8 parts.
Clay (pure as possible)2 parts.
Horse dung1 part.