used in the cylinder. Olive oil is a fine lubricant, and is used
largely in the Italian and Spanish navies.

Many special brands are probably good oils and safe to use, but
there is no need of staking one's trip upon any particular brand.

All good steam-cylinder oils contain animal oil to make them
adhere to the side of the cylinder; a pure mineral oil would be
washed away by the steam and water.

To illustrate the action of oils and water, take a clean bottle,
put in a little pure mineral oil, add some water, and shake hard;
the oil will rise to the top of the water in little globules
without adhering at all to the sides of the bottle; in short, the
bottle is not lubricated. Instead of a pure mineral oil put in any
steam-cylinder oil which is a compound of mineral and animal; and
as the bottle is shaken the oil adheres to the glass, covering the
entire inner surface with a film that the water will not rinse
off.

As there is supposed--erroneously--to be no moisture in the
cylinder of a gas-engine, the use of any animal oil is said to be
unnecessary; as there is moisture in the cylinder of a
steam-engine, some animal oil is absolutely essential in the
cylinder oil.

For the lubrication of chains and all parts exposed to the
weather, compounds of oil or grease which contain a liberal amount
of animal fat are better. Rain and the splash of mud and water
will wash off mineral oil as fast as it can be applied; in fact,