When all persons having either debits or credits to be paid in New York and in London, respectively, are dealing with the banks in these cities, and the banks and special exchange brokers are constantly buying and selling these bills, a market is created for London exchange in New York (and conversely in London), and a much easier and more nearly complete cancelation of indebtedness results. In effect, all the debits and credits between the two countries are merged into one big ledger balance, and the international shipment of gold bullion finally made is just the amount needed to balance the accounts payable at the time. Industrial indebtedness is represented in various forms: bills of lading for goods shipped, drafts made by the creditor on his debtor for goods shipped or property sold, checks or letters of credit for travelers, bonds and notes public and private. These are the objects dealt in by the bankers who are the agents to carry on the work of exchange. The balance of foreign exchanges is of essentially the same nature as the domestic cancelation of indebtedness. It is going on constantly between the two merchants in the same town, between two banks in the same town who represent groups of merchants, between men in neighboring towns, and between distant states like New York and California.[8] The price of exchange to the individual is reduced by the specializing of the business in the hands of a few dealers, permitting the cancelation of indebtedness or offsetting of exchange, and greatly reducing the amount of bullion to be transported in making the payments. The cost to the bank of providing this exchange for its customers varies as conditions change, but in any case is not great, so that in domestic business when any charge is made it is usually at a fixed rate, and is mainly for the service.