As the petroleum is ordinarily mixed with more or less water when brought to the surface, it is thrown first into a tank, and the superior gravity of the water causing it to sink to the bottom, it is drawn off from beneath, and the petroleum placed in barrels. These tanks are of all sizes, ranking from thirty to two thousand barrels each.
For the present, wells that were formerly pumped at a profit are biding their time; for at present prices of oil operations upon them would be ruinous. This renders the computation of the weekly yield of the Oil Creek region comparatively easy. There are at the present time not far from one hundred flowing wells along the valley of the creek, producing probably on an average about forty thousand barrels per week. A portion of this is refined in the county, but by far the largest part is shipped to a distance, either by the Alleghany River by way of Pittsburg, or by the Philadelphia and Erie or Atlantic and Great Western Railroads to the Eastern markets.
The necessities of the trade have given rise to many ingenious inventions in getting the oil to market. The wells extend along Oil Creek for a distance of about fourteen miles from its mouth. The ground is not favorable for land carriage, as the valley is narrow and the stream tortuous. The creek itself is too small for navigation under ordinary circumstances, and a railroad with steam power would be in the highest degree dangerous. To compensate for all these difficulties, a system of artificial navigation has been adopted. Throughout the whole distance, at intervals of perhaps a mile, dams have been constructed across the creek, with draws in the centre, that can be easily opened at the proper time. In this way 'pond freshets' are arranged one or two days in a week. By the appointed time, all persons having oil to run out of the creek have their boats ready, and as the water from the upper dam raises the creek below, the fleet of boats sets out. Each successive dam raises the water to a higher level, and as the fleet proceeds, small at first, it increases until, as it approaches the river, it often numbers two hundred boats, bearing with them not less than ten thousand barrels of petroleum.
The advent of this fleet of boats to the mouth of the creek is in the highest degree exciting. As boat after boat rushes into the river, there is the dashing to and fro of the boatmen, and the shouts of the multitude on the shore. Here and there a collision occurs that often results in the crushing of the feebler boat, and the indiscriminate mingling of boatmen, fragments of the broken craft, oil, and fixtures in one common ruin. In this fleet the form and variety of boats beggars all description. Sometimes there is the orthodox flatboat, filled with iron-bound barrels, with an air of respectability hovering around it. Next will follow a rude scow, and close upon it an unwieldy 'bulk,' into which the oil has been pumped at the well. After this, perhaps, may be seen a rude nondescript, that surely was never dreamed of outside the oil region. It consists of a series of rough ladders, constructed of tall saplings. Between each pair of rounds in these ladders is placed a barrel of oil, floating in the water, but kept in position by its hamper. A number of these ladders are lashed together, until the float contains two or three hundred barrels of oil.
The bulks spoken of are about sixteen feet square and two or three feet in depth, divided internally into bulk-heads of perhaps four feet square, to prevent any undue agitation of the oil by the motion of the boat, and are sometimes decked over. These unpromising boats, as well as the ladder floats, are, during favorable weather, often run to Pittsburg with entire safety. Steamboats, however, run up to the mouth of Oil Creek during the time of high water, and afford the safest and most expeditious means of transportation.
As to the abundance of the supply in this region, there can be but little doubt. Wells seem at times to become exhausted, but it is from local causes. At times a cavity may be tapped that has been supplied from a very small avenue, and may be readily exhausted, but exhausted only to be refilled again. The fact that wells do not interfere with each other, even when but fifty feet apart, is evidence that the supply is not confined to a limited stratum, but is drawn from the great deeps beneath. The existence of the ancient oil pits, before alluded to, assures us that the supply has been continued for centuries; and observation confirms this, as we have noticed the hitherto unused treasure bubbling up silently through the crevices in the rocks and gradually evaporating amid the sands, or arising in the beds of the streams and floating down upon their surface. The history of the petroleum trade in other lands encourages us as to the abundance of the supply in our own. In the northern part of Italy, petroleum has been collected for more than two hundred years, without any intimation that the supply is being exhausted. In Burmah a supply has been drawn from the earth for an unknown period, and so far are these wells from exhaustion that they yield at the present time over twenty-five millions of gallons per annum. We may well suppose, then, that the treasure brought to light in such abundance in our day will not be readily exhausted—that as the coals are found in illimitable abundance for fuel as the forests fail, petroleum for illuminating purposes will be found in like profusion.
We have said that the petroleum trade has known no infancy, but has sprung at once into maturity. The oil wells of Venango County alone produced, during the first year of their operation, more oil than the entire product of the whale fisheries during the most favorable and prosperous year in their history. At the present time, after a lapse of little more than two years, the daily product of the wells on Oil Creek alone is computed to be over six thousand barrels. And in this neighborhood the quantity might be wellnigh doubled, were it not for the low price the product commands.
Petroleum differs in its characteristics in different localities. It is usually heavier in the shallow wells than in those that are deeper. Ordinarily it is of a greenish hue, that changes to a reddish as the oil becomes lighter and more evaporative. It is all characterized by a strong and pungent odor peculiar to itself. The gravity of the various kinds of oil is ascertained by the oleometer. The lighter oils are found on Oil Creek, and are about 40° to 46° Baumé; at Franklin, from 30° to 32°.
It is difficult to speak of the uses of petroleum at the present time, for these uses have not yet been fully developed. In its refined state it is preëminent as an illuminator. In this character it yields the palm to gas in matters of convenience and neatness, but is superior to it on the score of general adaptation and economy. Besides, the quality of the light is superior to that of gas, being soft, mild, tranquil, and exceedingly white. In the rural districts, where coal gas is impracticable, it would be an intolerable calamity to be obliged to return to the use of the old tallow candle that was the main dependence in years gone by. As an article of fuel, it has been used to some extent in the oil regions, but the appliances have been so rude that its use has not been general. When proper machinery shall have been invented, no doubt it will be a most important item of fuel in ocean navigation as well as in railway travel, conducing alike to economy of space and to ease of manipulation.
In the manufacture of gas it has already been brought into successful use, both in this country and in England, and has been found most valuable alike in the quality of the product and in the economy of its production.