Thomas Jefferson to Thomas Freeman, 16 November 1805
To Thomas Freeman
Washington Nov. 16. 05.
Th: Jefferson asks the favor of mr Freeman, as he will be in the Mathematical shops in Philadelphia to endeavor to procure for him an accurate compass for surveying, with 2. pair of sights moving concentrically, an outer graduated circle with a Nonius to take angles accurately without regard to the needle, with it’s ball & socket & staff. he believes they are called Circumferentors but is not certain. he has seen them made to turn down vertically, so as to take altitudes with a plummet: but this is not material to his object. if mr Freeman finds such a one which he thinks good, if he will be so good as to drop a line mentioning the price & where to be had, Th:J. will immediately remit the price to the person & desire it to be sent on. he salutes mr Freeman with respect.
RC (PPAmP: Sol Feinstone Collection of the American Revolution); addressed: “Mr. John Freeman now in Philadelphia” with notation “to the care of mr Patterson.” PoC (DLC); endorsed by TJ with “Thos” interlined in place of “John.” Enclosed in TJ to Robert Patterson of this day.
TJ listed the surveyor’s compass, also known as a circumferentor, as a “common Theodolite or Graphometer” of eight inches diameter in his inventory of “Mathematical Apparatus” (MS in MHi). He noted drawing $54 on the Bank of the United States to forward to Freeman for the instrument on 12 Dec. (, 2:1170; , 360-1).