Carter's "new mill," completed in 1773, had a capacity of 25,000 bushels a year and cost him £1,450 in materials and wages. Carter also built in connection with the mill a bake house, the two ovens of which would bake one hundred pounds of flour at each heating. And he hired a cooper to "get up 10 good flower caskes per day" at an annual salary of £30.
Carter estimated his total outlay to keep the mill running at £5,000 per year, but the return was correspondingly great. The mill was a success from the start, and the Revolution soon added to its importance and its business. For several months in 1780 the mill worked eighteen hours a day grinding for the state, and Carter received six bushels of corn a day in toll. After 1785, however, Carter found it unprofitable to work the mill himself, and leased it to other operators.
Although on a smaller scale, George Washington also engaged in merchant milling. His Dogue Run mill, formerly a plantation mill only, was rebuilt in 1769 as a merchant mill. He installed a pair of French burr stones to grind the export flour, while a pair of Cologne stones did the country work and ground Washington's own crops. Washington also provided a nearby dwelling house and garden for the miller and his family, who could raise chickens for their own table but never for sale.
"The whole of my Force," Washington wrote in 1774, "is in a manner confind to the growth of Wheat and Manufacturing of it into Flour." Some of the wheat he proposed to sell in London if the price were right, if the freight and commission charges were not too high, and "if our Commerce with Great Britain is kept open (which seems to be a matter of great doubt at present)." He did ship some flour directly to the West Indies but disposed of most of his "superfine flour of the first quality" through merchants in Norfolk and Alexandria.
Washington, like Carter and other Virginia merchant millers, felt the loss of West Indian markets after the Revolution. But he continued his interest in milling into the better times that followed the establishment of a stable national government. Washington, in fact, received one of the first licenses to use the milling improvements invented by the Delaware millwright, Oliver Evans. As late as 1799, the year of his death, he wrote that "as a farmer, Wheat and Flour constitute my principal Concerns."