GW’s miller was William Roberts, a Pennsylvanian who had signed articles of agreement with Lund Washington 13 Oct. 1770 engaging himself to run the new mill at Mount Vernon for £80 a year plus the privilege of feeding a cow and raising domestic fowl at GW’s expense (DLC:GW). Roberts was highly skilled in the business of grinding grain, a delicate art requiring great judgment in fixing the speed and interval of the millstones to produce good-quality flour with minimum waste. He was also, like John Ball, a capable millwright who could keep the mill in proper working order, and when he was not grinding grain, he could work in the nearby cooper’s shop making barrels needed for flour and other products. Aided by an apprentice miller whom he had brought with him. Roberts worked diligently and honestly for GW for several years, but an addiction to liquor eventually proved to be his undoing (GW to Robert Lewis & Sons, 6 Sept. 1783, and 12 April 1785, DLC:GW).