designs of the Grand Duke Ferdinand himself, for he used them in 1644 when he was experimenting on the artificial hatching of eggs, and in meteorological observations. In 1646 Torricelli showed thermometers of this construction to the distinguished French traveler, Monconys.
The members of the academy used these thermometers, especially the one of 50 degrees which they found the most convenient and accurate, in a variety of experiments with freezing-mixtures and the reflection of cold by a concave glass. The thermometer scales can be thus compared:
| Academy thermometers. | ||
| No. 1 | No. 2. | Fahrenheit. |
| 73 | 37.5 | 96 |
| 49 | 13.5 | 32 |
| −8 | −8.5 | 0 |
In the year 1829 a number of Florentine thermometers were found in a shop in Florence by Antinori, and Libri ascertained their scales to have the following values: (Ann. chim., 45, 354).
| Flor. | C. | Fahr. |
| 13.5 | 0 | 32 |
| 0 | 18.7 | 65.6 |
| 50 | 55 | 131. |
The academy's thermometers were a great
