Storage is, of course, still necessary, because the production frequently exceeds the capacity of the refineries and the demands of the market. But the storage is done chiefly in enormous tank farms owned by the big oil companies, with the Standard naturally as the most important. Huge boiler iron tanks, nearly a hundred feet in diameter, and thirty feet high, holding about 35,000 barrels, are the usual type now adopted. A single farm often contains two or three scores of such tanks, with the storage capacity ranging up to millions of bar rels. In this way the surplus production is readily taken care of, without hindering any operator from producing as fast as possible in order to keep his neighbors from getting more than their share.
The unqualified success of the pipe-line system in the United States has led to its introduction into every important oil field in the world. The Baku operators, quick to profit by any American success, introduced pipe lines from the wells to the refin eries about 1879, and, curiously enough, went through practically the same kind of struggle with the native teamsters as marked the laying of the first line in this country. In the same way in Galicia and Roumania, in Japan, in Burma, and in the Dutch East Indies the pipe line has begun to replace the primitive methods of handling, and has put the industry on a modern basis.
The production of petroleum in this country has always been greater than the demands of home consumption, so that for many years much of the supply has been forced to seek a market in foreign countries. As the foreign shipments grew, the methods of over-sea carriage began to be fully as important as the other branches of the transporta tion system. Shipments abroad for several years after export trade began, were all made in barrels, under even greater disadvantages than were en tailed by the use of barrels at home.
Bulk shipments had solved the problems of do mestic transportation. It was, therefore, entirely logical to argue that it would serve the same purpose in the export trade. If bulk barges could be operated on the Allegheny River, there was no apparent reason why the same thing could not be done on a larger scale in the trade with Europe. About 1870 several wooden sailing vessels, fitted with tanks in their holds, had been tried in the trade between this country and European ports, but with only partial success. In 1872 the steamer Vaterland was specially constructed to carry bulk cargoes of petroleum, but the fear that the presence of oil in the hold would interfere with the passen ger traffic prevented the tanks ever being used.
Finally, about 1879, several sailing vessels, built for the trade, successfully carried cargoes of oil in bulk to Continental ports, and marked the begin ning of a new era in the marine transportation of petroleum. Other similar vessels soon followed,
and before long tank steamers were also added to the fleet of bulk carriers. The problem of securing crews, however, was for a time a serious obstacle to the success of the steamers. Sailors, in general, regarded it as suicidal to ship on a vessel where oil and fire were companions, and many a sailor was taken aboard with his senses dulled by poor whisky. There was some reason for this aversion to the tank steamer, it is true, for fires were fre quent, both in port and on the high sea, and occa sionally a vessel left port with a cargo of oil never to be heard from again.
As in the case of the early pipe lines, the advan tages of bulk transportation by water were far too great for any obstacle to remain long in its way. Imperfections in constructing the vessels were remedied, improvements were adopted, and one change after another led to the evolution of the modern steel "tanker," divided into separate com partments by sets of longitudinal and transverse bulkheads. Steamers, safeguarded by modern pre cautions, now carry millions:ot '*alions of Oil vdt)f little more danger of fire than in th'e'cage of other cargoes. Considerable care is, of course, required concerning the nature of the lights on board the vessel, the use of matches, and smoking among the crew, particularly when receiving or discharging cargo, and when cleaning the tanks; but the same thing is more or less true of any kind of combus tible cargo.
The tank vessel is unquestionably one of the most important inventions in the whole history of petro leum, for it alone has made it possible for Ameri • cou• pil§ to compete in much of the world's trade okaitist.: A 1-oini..vthdir countries. Nowadays, as • • • .
soon as a tanker nears port, word is sent to the refinery, and by the time the vessel is tied up at the dock the cargo of oil is all ready to be taken on board. Powerful pumps are started, and, while provisions and supplies for the voyage are being secured, the tanks are filled. Half a day suffices to put aboard a cargo that would have taken a big gang of men a week to stow in the days of shipment by barrel on the slow sailing vessels. Thirty years ago bulk carriage by sea was still in the experimental stage. Now hundreds of ves sels of every description, hailing from all coun tries, are carrying cargoes in bulk to every corner of the world; steamers, sailing vessels, and barges transporting millions of barrels of oil annu ally. A multitude of stevedores and coopers have lost a profitable employment, but the advantages to the petroleum industry have been beyond measure.