the oil or not, so that under these contracts the Standard Oil Company members would pay no more than 44 cents per barrel as freight to the carrier, while their competitors would pay $1.50, and of this last sum the railways were to pay back to the combination $1.06 per barrel."[131] Though this monstrous conspiracy was quickly unmasked, and the South Improvement Company lost its charter, secret negotiations with the railway companies enabled the Standard Oil Companies to strengthen themselves by this system of rebates paid out of the pockets of their business rivals. Chiefly by means of these and other discriminating contracts they were enabled to enlarge their sphere of activity, and making full use of their growing capital, succeeded in destroying or absorbing their competitors, until, as early as 1875, they held a practical monopoly of the refineries of the interior. No fewer than seventy-four refineries are stated to have been bought up, leased, or bankrupted by the Standard Oil Company in Pennsylvania alone in the course of its career. Until about 1878 the chief source of power of the company seems to have been the alliance with the railroads and the local monopolies obtained by buying up or crushing rival businesses. But the president, Mr. Rockefeller, and his associates were men of keen business ability, who understood how to make use of the inventive genius of the abler employees who passed into their service, and of the improvements in method of production and distribution of oil which were suggested. In the next few years the company were enabled to effect enormous economies in the storage and conveyance of oil. Pipe lines were laid down connecting New York, Philadelphia, Baltimore, Buffalo, Pittsburg, Cleveland, and Chicago, and a network of feeding lines joining the sources of supply. Thousands of huge tanks were erected for holding surplus stores; a large number of agencies were established along the sea-shore with storage attached. Further considerable economies were effected by the undertaking of the manufacture of barrels and cans and other subsidiary articles required in the trade. At the close of 1881 the owners of the entire capital of fifteen corporations and parts of the stock of a number of others, the latter chiefly trading companies, established the Trust. The number of shareholders thus associated was forty, and they placed their stocks in the hands of nine of their number as trustees, who continued to administer the whole business, paying interest upon the certificates which represented the stock of the several shareholders until March 1892, when the Trust was legally dissolved. The legal dissolution of the Trust has not, however, materially impaired its economic unity and power; on the contrary, it has extended in the United States its monopolic control of the market, and has already established a strong control over several European markets for the sale of oil, and over the chief natural sources of supply.