The Wealth of Nations by Part 2 Chapter 2 Page 44

If there are two merchants, one in London and the other in Edinburgh, who employ equal stocks in the same branch of trade, the Edinburgh merchant can, without imprudence, carry on a greater trade and give employment to a greater number of people than the London merchant.

The London merchant must always keep by him a considerable sum of money, either in his own coffers, or in those of his banker, who gives him no interest for it, in order to answer the demands continually coming upon him for payment of the goods which he purchases upon credit. Let the ordinary amount of this sum be supposed five hundred pounds. The value of the goods in his warehouse must always be less by five hundred pounds than it would have been had he not been obliged to keep such a sum unemployed. Let us suppose that he generally disposes of his