Thomas Jefferson’s Notes on Thermometer Calibration, [ca. 21–22 January 1820]
Notes on Thermometer Calibration
[ca. 21–22 Jan. 1820]
mercury zero correctd | Metallic | |
30 | . | |
29 | . | |
28 | . | |
27 | . | |
26 | ||
25 | ||
24 | ||
23 | ||
22 | . | |
21 | ||
20 | ||
19 | ||
18 | 18¾ | |
17 | . | |
16 | . | 17¼ 17. |
15 | 16¼ | |
14 | 15.¼ | |
13 | 15. 15. 15¼ 14½ | |
12 | ||
11 | 13. 13⅓ | |
10 | 12 | |
9 | 11 | |
8 | 11. 10 | |
7 | 9. 9¼ | |
6 | 9. 9¾ 8¾. 9. 9½ | |
5 | 8. 8 | |
4 | 7. 7. | |
3 | 6¼. 7. | |
2 | 5. 5½ 5½ 5½ 6 | |
1 | 4¾ | |
0 | 4¼. 4. | |
1 | +3. +2 | |
2 | +2. 1½ +2. | |
3 | +1. 1. | |
4 | 1¼ | |
5 | − ½ ¾ | |
6 | 1½ | |
7 | ||
8 | 3¼. | |
9 | ||
10 | ||
11 | ||
12 | ||
13 | ||
14 |
Reaumur1
the 0. correctd mercury |
do metallic | |
1820. | ||
Jan. 21 | ||
− | 3½ | +½ |
+1 | +4¾. | |
22. | +1½ | +5 |
MS (MHi); on verso of reused address cover of David Watson to TJ, 26 Feb. 1819; filed with TJ’s Weather Memorandum Book, 1802–16; entirely in TJ’s hand; undated.
A metallic or bimetallic thermometer “indicates temperature by differential expansion and contraction of composite metal bars” ( ).
1. Text from this word on is at bottom of page and oriented upside down with relation to preceding table.