The consignment system developed along with the system of casual trading, and it also operated upon the practice of the ships collecting cargo from the various plantations. Importation was based on the same idea: the ship which gathered the planters' tobacco usually brought goods from abroad. Originally the merchant acted only as the agent of the planter. He advanced him the total cost necessary to export and market the crop abroad, sold the crop on his client's account and placed the net proceeds to the planter's credit. Soon the merchant was advancing the planter goods and money beyond the amount of his net receipts; the planter frequently discovered that he was at the merchant's mercy and was forced to sell on the merchant's terms. To make matters worse, the tobacco was sold by the merchants to retailers in England on long term credit at the planter's risk. If the retailer went bankrupt, or his business failed, the planter not only lost his tobacco but still had to pay the total charges, freight, insurance, British duties, plus the agent's commission, which amounted to about eighteen pounds sterling in 1730. Planters frequently complained that their tobacco weighed much less in England that it did when it was inspected and weighed in the colony. There were reports that the stevedores were supplying certain patrons in England with tobacco of superior quality obtained by pilfering. An agent in England was certainly not apt to look after a planter's crop as though it were his own. The gradual destruction of the fertility of the soil in the Tidewater country and the expansion of the tobacco industry into the back country made direct consignment less feasible. This, and the various other causes of dissatisfaction with the consignment system, led to the system of outright purchase in the colony. This new procedure was carried on largely by the outport merchants, especially the Scottish, who were doing quite a bit of illicit trading before the Union of 1707. Since the Tidewater business was controlled largely by the London merchants, the new Scottish traders penetrated the interior and established local trading posts or stores at convenient locations, many of which became the nuclei of towns. After the Union their share of the trade increased very rapidly, and at the beginning of hostilities in 1775 the Scots were purchasing almost one-half of all the tobacco brought to Great Britain. On the eve of the Revolution only about one-fourth of the Virginia tobacco was being shipped on consignment.