Thomas Jefferson to Amos Hamlin, 1 April 1818
To Amos Hamlin
Monticello Apr. 1. 18.
I am indebted for your letter of Jan. 12. which was exactly 2½ months in getting to my hands, & brought me the favor of your meteorological observations which bear the marks of great care and accuracy. I believe there is not a single person in this part of our country who attends to this subject, so that I am not able to offer you any thing from others. I kept pretty exact tables for a space of 7. years & then discontinued them. I state below some of the results which may perhaps be acceptable to you with the assurance of my great respect
Th: Jefferson
| therm. | fall of rain | |||||
| Jan | 36. | 3.66 | winds | |||
| Feb | 40 | 3.47 | N. | 61 | . | |
| Mar. | 46 | 2.92 | NE. | 29 | ||
| Apr. | 56½ | 3.59 | E | 15 | ||
| May | 61½ | 5.60 | SE. | 16 | ||
| June | 72 | 3.47 | S. | 60 | ||
| July | 75 | 6.56 | S.W. | 66 | ||
| Aug | 73 | 4.06 | W. | 47 | ||
| Sep | 67 | 5.96 | N.W. | 71 | ||
| Oct | 57 | 3.40 | 365 | |||
| Nov. | 45½ | 2.92 | ||||
| Dec. | 37½1 | 1.55 | ||||
| 55½ | 47.222 |
the greatest cold in the 7. years was 5½° above zero
the greatest heat was 94½°
the average temperature of the 7. years was 55½°
our coldest springwater is 54½ when the outer air is 75°
the average of a winter’s3 snow was 22½ I. covering the ground 22. days.
PoC (DLC); salutation missing, possibly due to polygraph misalignment; at head of text: “Mr Amos Hamlin”; endorsed by TJ.
For the pretty exact tables TJ kept between 1810 and 1816, see his Analysis of Weather Memorandum Book, Jan. 1817.
1. TJ’s Analysis: “37.”
2. Correct sum is 47.16. TJ’s Analysis, which gives average rainfall to three decimal places, renders the total as “47.218.”
3. Preceding two words interlined.
Index Entries
- Durham, N.Y.; meteorological observations in search
- Hamlin, Amos; and meteorological observations search
- Hamlin, Amos; letter to search
- Jefferson, Thomas; Writings; Analysis of Weather Memorandum Book search
- Jefferson, Thomas; Writings; Weather Memorandum Book search
- meteorological observations; by A. Hamlin search
- meteorological observations; by TJ search
- Monticello (TJ’s Albemarle Co. estate); weather recorded at search
- New York (state); meteorological observations in search
- scientific instruments; thermometers search
- springs; temperature of as climate indicator search
- thermometers; TJ uses search
- weather; cold search
- weather; heat search
- weather; rain search
- weather; snow search
- weather; temperature readings search
- weather; TJ’s Analysis of Weather Memorandum Book search
- weather; wind search
- Weather Memorandum Book (Thomas Jefferson) search