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 the Volga to Russian markets. Great Britain takes about one-third; about the same amount is shipped to Port Saïd for China, India, and other Asian markets; the rest is consumed in central Europe.
Petroleum Products.—The various constituents of crude petroleum differ greatly in character, some being much more volatile than others. They are separated by distillation at different temperatures. By this process naphtha, rhigoline, gasoline, benzine, and other highly inflammable products are obtained in separate receivers. By a similar process the illuminating or refined oil and the lubricating oils are also separated. The residuum consists of a gummy mass from which paraffine and petroleum jelly are extracted.
Naphtha usually contains several volatile compounds, including benzine and gasoline. It is used as a solvent of grease and also of crude india-rubber, but chiefly the manufacture of illuminating gas.
Kerosene is the name commonly given to the refined oil. A good quality should have a fire test of not less than one hundred and fifty degrees; that is, when heated to that temperature, it should not give off any inflammable gas. This test is now mandatory in most States.
Lubricating oil is used almost wholly for the lubrication of heavy machinery. It varies greatly in composition and quality.
Paraffine or petroleum wax has largely superseded beeswax; it is used mainly in the manufacture of candles and as an insulator for electric wires. A native mineral paraffine, known as ozocerite, is mined in Utah and Galicia; it is used as an insulating material.
"Vaseline," "cosmoline," or petroleum "jelly" is very largely used in pharmacy as the basis of ointments and also as a lubricant for heavy machinery.