"...no idea why, given that background, he had been made an overseer."
quote from Slave Labor in the Capital page 137:
Imagine Isaac Naismith's shock when his recommendation from General John Davidson, prominent member of the Executive Council of the State of Maryland, for a job on the team building the nation's capital resulted in his being hired as an overseer of laborers, most of them hired slaves, at the President's house. Worse still, he was paid so little he couldn't support himself and his small family.
Despite the educated hand writing the letter, it is difficult to read but it is clear that he thought being an overseer was quite a let down given his education and 11 years of work experience.
A few months later Naismith complained that he was not making enough to support his family and asked permission to supplement his income by "keeping a small set of books" for another concern which would only take two days a week.. In 1797 the commissioners had two overseers at the Capitol and judging from Naismith's letter, two at the White House. Naismith argues that one overseer can attend to the laborers and issue rations and that he, the other overseer, will still be able to take care of accounts and receipts for materials.