Enclosure: Thomas Jefferson’s Summary of Weather Observations, 1810–1816, [ca. 11 April 1818]
Enclosure
Summary of Weather Observations, 1810–1816
[ca. 11 Apr. 1818]
| 1. | the greatest & least height of the thermometer every day. |
| 2. | the greatest, least, & mean height of the thermom. in every month, with the mean of each year, & the mean of the 7. years, which last1 was 55½°. |
| 3. | the minimum & maximum of the whole term, to wit 5½° and 94½° |
| 4. | the number of freezing nights in a winter [50.] & of freezing days [10.] |
| 5. | how long fires are necessary in our apartments. to wit 4. months constant & evening & morning one month before & after that term. |
| 6. | the earliest frost in Autumn Oct. 72–26 and the latest in spring Mar. 19–May 15 |
| 7. | the earliest ice in Autumn Oct. 24–Nov. 15. and latest in spring Mar. 8–Apr. 10. |
| 8. | the quantity of water falling in a year. average 47.218 I. |
| 9. | the number of rains in the year. 89. |
| 10. | the number of fair days. average 5. to the week. |
| 11. | the quantity of snow 22½ I. average; covers the ground 22. days. |
| 12. | the number of days each wind prevails thro’ the year. |
| 13. | the flowering of plants, ripening of their fruit, the coming to table of the productions of the garden, arrival of birds, insects Etc. |
| 14. | the temperature of the springs. 54½° the outer air being at 75.° |
| 15. | the latitude of the place of observation [Monticello] 37°–57′–51″–26‴ |
| extract from No 13. | |||||
| the Peach blossoms | Mar. | 9. | to Apr. | 4. | |
| the tick appears | 15 | 2 | |||
| the house Martin | 18 | 9 | |||
| Asparagus comes to table | 23 | 14 | |||
| the Lilac blooms | Apr. | 1. | 28 | ||
| the red-bud blooms | 2 | 19 | |||
| the whip-poor Will is heard | 2 | 21 | |||
| the dogwood blossoms | 3 | 22 | |||
| the Locust blossoms | 25 | to May | 17. | ||
| garden pea comes to table [unforced] | May | 3. | 25 | ||
| strawberries ripe | 3. | 25 | |||
| fireflies appear | 8. | ||||
| cherries ripe | 18. | 25 | |||
| wheat harvest begins | June | 21. | 29 | ||
| cucumbers at table [unforced] | 22 | to July | 5 | ||
| peaches ripe | July | 7. | 21. | ||
| Catydids or3 sawyers heard | 14 | 20. | |||
| average of every month. | prevalence of the several winds stated in days of a year. |
||||||
| therm. | rain | ||||||
| Jan. | 36 | 3.66 | |||||
| Feb. | 40 | 3.47 | N. | 61. | |||
| Mar. | 46 | 2.92 | N.E. | 29 | |||
| Apr. | 56 | ½ | 3.59 | E. | 15 | ||
| May | 61 | ½ | 5.60 | S.E. | 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. | 45 | ½ | 2.92 | ||||
| Dec. | 37 | 1.56 | |||||
MS (MHi: Mary Anna Bigelow Autograph Collection); subjoined to RC of covering letter; entirely in TJ’s hand; undated; corner torn, with missing text supplied from PoC; brackets in original. PoC (DLC); subjoined to PoC of covering letter.
This document is a summary of TJ’s Analysis of Weather Memorandum Book, Jan. 1817.
1. Word interlined.
2. Reworked from “27.”
3. Preceding two words (more commonly, katydids) not in TJ’s Analysis.
Index Entries
- asparagus search
- Bigelow, Jacob; TJ sends weather observations to search
- birds; and weather search
- birds; house martins search
- birds; whip-poor-wills search
- cherries; as crop search
- crops; strawberries search
- cucumbers search
- dogwood search
- fireflies search
- food; asparagus search
- food; cherries search
- food; cucumbers search
- food; peaches search
- food; peas search
- food; strawberries search
- grasshoppers search
- insects; and weather search
- insects; fireflies search
- insects; grasshoppers search
- insects; sawyers (beetles) search
- insects; ticks search
- Jefferson, Thomas; Writings; Analysis of Weather Memorandum Book search
- katydids search
- latitude; calculations for Monticello search
- lilac search
- locust (tree); common search
- martins, house search
- meteorological observations; by TJ search
- Monticello (TJ’s Albemarle Co. estate); latitude of search
- Monticello (TJ’s Albemarle Co. estate); peas grown at search
- peaches; harvest of search
- peaches; trees search
- peas; grown at Monticello search
- plants; and weather search
- redbud search
- sawyers (beetles) search
- scientific instruments; thermometers search
- springs; temperature of as climate indicator search
- strawberries; as crop search
- thermometers; and meteorological observations search
- ticks search
- trees; dogwood search
- trees; locust, common search
- trees; peach search
- trees; redbud search
- weather; cold search
- weather; fair search
- weather; frost search
- weather; heat search
- weather; ice 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
- wheat; as crop search
- whip-poor-wills search

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