d in solid rock near
Titusville, Pa. The venture proved successful, and in a few years
petroleum mining became one of the great industries of the United
States.

Petroleum is known to exist in a great many parts of the world; the
United States and Russia, however, produce practically all the
commercial product; a very small amount is obtained from a horizon on
the south slope of the Carpathian Mountains, situated in Rumania and
Galicia, Austria-Hungary. There are also a few producing wells in Peru,
Germany, Italy, Burma, Argentina, and Sumatra.

[Illustration: PETROLEUM FIELDS IN THE UNITED STATES]

In the United States the largest horizon is that of the Appalachian
region. Since 1859 it has produced more than forty million gallons of
crude oil. The Lima, Ind., horizon produces about twenty million
barrels. The California and Texas horizons have become very important
factors. The crude petroleum is transported partly in tank cars, but
mainly by means of long lines of pipe, flowing from one pumping station
to another by gravity. There are pipe-line terminals on the Great Lakes
and at Pittsburg, but the principal are at the refining and exporting
stations in New York, Philadelphia, and on the Delaware River.

A considerable amount is exported to European countries to be there
refined, but in the main the crude oil is refined before exporting it.
Some of the refined oil is exported in barrels, and some in tin cases;
the greater part, however, goes in tank steamers, and from these it is
pumped into tank cars to be distributed. Most of the product is
controlled by the Standard Oil Company, and it reaches nearly every
country in the world. It is carried into Arctic regions on sledges, and
over the African deserts by caravans. Great Britain, Germany, and the
Netherlands are the chief purchasers and distributors. The value of the
entire product is about one hundred and eighty-five million dollars.

The Russian oil-producing region is on and near the Apsheron peninsula,
a small area of Trans-Caucasia, that extends into the Caspian Sea; the
region is commonly known as the Baku field, and in 1900 the production
of crude oil surpassed that of the United States. The petroleum is
conveyed by pipe lines to the refineries at Baku. From this port it is
shipped in tank cars by rail to Batum, whence it is conveyed to the
various European markets. A considerable part of the product is sent by
tank steamers to Astrakhan, and thence up