2pp, 14 1/4 x 12 in. (sight) framed to 15 1/4 x 13 in. (unexamined outside frame, creasing, tears at folds, small losses not affecting text). Addressed to Richard Wister, a merchant on Market Street in Philadelphia.

Chancellor writes to Wister with news of his arrival in London, as well as his ongoing studies with surgeons and at hospitals to advance his medical knowledge. In a postscript below his signature, Chancellor adds: "If Dr. Bond or Greme [Graeme] should die put in for my being the person appointed to search the Dutch ships as I understand the trade will be largely carried on." Chancellor may refer here to the continuation of the slave trade despite the ongoing French and Indian War. The position which he seeks in Philadelphia is an appointment by the assembly as an inspector of unhealthy ships, specifically ones arriving with cargo consisting of enslaved men, women, and children from Africa.

William Chancellor worked as a doctor on board the sloop "Wolf" when it departed New York in September 1749 as part of a 20-month slaving voyage to the coast of West Africa. The surviving volume of the diary he kept while on board documents the misery he witnessed amongst the captured Africans. That diary, along with one other letter written to a friend on 6 September 1761, are the only other manuscripts by Chancellor known still to exist.