200,000 acres. Ohio and West Virginia also contribute something to the general oil-supply.
To whatever cause the formation of petroleum is due (and it is generally attributed to the decomposition under enormous pressure of vast deposits of animal and vegetable matter), it is now ascertained that it exists in rocks of nearly all geological ages. Upper and Lower Devonian, Silurian, and Tertiary, have all been proved to be oleiferous. One thing worthy of note is, that the springs are generally found near the base of great hills. We have already seen that those of Venezuela lie among the spurs of the Cordilleras. Those of Pennsylvania lie chiefly near the Alleghanies, and the great oil-region of the Caspian is overshadowed by the Caucasus.
In the year 1876 (seventeen years after Colonel Drake had bored his first well) it was estimated that 20,000 wells had been sunk in Pennsylvania and West Virginia at a cost of $190,000,000, the oil produced being valued at $300,000,000 at the wells—cost of carriage to the seaboard adding one fourth to the value of an oil-cargo. In 1879 the production of oil in the United States was estimated at about 15,000,000 barrels, equal to 600,000,000 gallons. In 1880 upward of 400,000,000 gallons, valued at $46,000,000, were exported from the States, irrespective of the enormous home consumption.
Very remarkable is the organization whereby an elaborate system of iron pipes connects all the wells in the most remote districts of Petrolea with enormous tanks, wherein the oil from many wells is stored and is thence conveyed by main pipes to the nearest railway-station, where it runs into another series of great reservoirs, thence to be transferred to the locomotive tanks or oil-wagons. These are cylinders resembling great steamboat funnels laid lengthwise on the wagon. From the center of each cylinder rises a large iron cupola, constructed to allow for the expansion of the oil should it become heated. Such wagon-trains are about as dirty and greasy looking concerns as can well be imagined.
In many cases their services are dispensed with, and the main pipes—which have a diameter of from four to six inches—are carried direct to the great refineries. One of these at Cleveland is one hundred and seven miles distant from the wells which feed it; another at Buffalo is distant seventy-eight miles; and that at Pittsburg is thirty-eight miles from its source of supply. Two great main pumps are led three hundred miles to Bayonne on the seaboard of New York Bay, and there deliver their cargo ready for shipping. Pumping-engines working at intervals of twenty-five miles give an impetus to the flow of these oil-streams.
This pipe business is all in the hands of two great companies; and some idea may be formed of the vast scale on which they work, from the fact that the principal company—distinguished as "The United Pipe Lines Company"—owns three thousand miles of pipes, and
