Thomas Jefferson Papers
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Thomas Jefferson to George Wyche, 10 November 1818

To George Wyche

Monticello Nov. 10. 18.

Sir

Age and it’s consequent infirmities of body & relaxation of mind, oblige me to excuse myself from all correspondence. I am no longer equal to it. I will answer however your enquiries respecting my admeasurement of the heights of the peaks of Otter. this was done about 3. years ago with an excellent Ramsden’s Theodolite of 3½ I. radius, having a Nonius dividing the degrees to 3′ minutes but shewing distinctly enough to 1½′ with two telescopes & cross spirit levels. I got a base of 1¼ mile along the low grounds of the Little Otter in the lands of mr Clarke & mr Donald, nearly parallel with the two mountains and about 4. miles from the points in their base vertically under their summits. there was a descent of 15.f. in the length of the base, which was taken into calculation. I got also a cross base of 55100 of a mile, crossing the other and pointing directly to the sharp peak. I found the height of the sharp peak above the bed of the river 2946½ feet, that of the flat peak 3103.½ f. the distance between the two summits 9507¾ f.

Two observations with a Sextant gave for a mean of the latitude of the sharp peak 37°–28′–50″.

Your indulgence will, I am sure, excuse the necessary brevity of this answer and accept the assurance of my great esteem & respect.

Th: Jefferson

PoC (MoSHi: TJC-BC); on verso of reused address cover of Mathew Carey & Son to TJ, 27 June 1818; at foot of text: “Mr Wyche”; endorsed by TJ.

Documents pertaining to TJ’s admeasurement of the Peaks of Otter are printed above at 10 Nov. 1815. His calculation of the latitude of the Sharp Peak of Otter is printed at 18 Sept. 1815.

Index Entries

  • altitude; calculations for Peaks of Otter search
  • Clark, Christopher Henderson; and height of Peaks of Otter search
  • Donald, Andrew; property of search
  • latitude; calculations for Peaks of Otter search
  • Peaks of Otter, Va.; altitude of search
  • Peaks of Otter, Va.; latitude of search
  • Ramsden, Jesse; theodolite of search
  • scientific instruments; sextants search
  • scientific instruments; theodolites search
  • sextant; TJ uses search
  • theodolites search
  • Wyche, George; as surveyor search
  • Wyche, George; letter to search