Instead of discharging debts to foreigners in the manner taken for granted by Christian,--viz., by transmitting money to a foreign land, as they would to the grocer's or the wine-merchant's in the next street, exporters and importers were early obliged, by an absurd enactment against the exportation of money, to devise some expedient for paying each other without using gold and silver. The most obvious way was to set against one another the values of things bought and sold, so that the balance was all that remained to be discharged. When it did not happen that the same firm at home had bought of the same firm abroad to whom it had sold, it was only necessary to find another firm at home which had bought in the same market abroad, and to exchange acknowledgments of debt, up to the amount at which the respective debts balanced one another; and these acknowledgments of debt served as money, in the same way as the promissory notes of bankers. In 1190, (which is the earliest recorded date of the practice of exchanging debts,) if an English merchant sold 100_l._ worth of cider into Holland, and his Dutch connexion had sold to another London merchant 90_l._ worth of fat cattle, the readiest way of paying the greater part of the debt was for the Dutchman to refer his cider-selling correspondent to his neighbour, the importer of cattle, for 90_l._: 10_l._ would still remain due; and as the Dutchman was prohibited from sending it in gold and silver, he would look about for some neighbour who had 10_l._ owing to him from England, and would say, "I will pay you 10_l._, if you will desire your debtor to pay the same sum to my correspondent on the other side the water." By this simple mutual accommodation, the expense and risk of sending large sums of money are avoided; the postage, and the stamp charged by government upon such transactions, are the only cost incurred; and the whole process of buying and selling is simplified to all parties.