|A Philo thermometer.|
This device was invented by Philo of Byzantium (c.280-220BC), and is said to be the first thermometer-like device.
Philo's thermometer design was described in a pamphlet published by him, and later read by those including Greek engineer Hero and German engineer Robert Fludd.
1. McGee, Thomas D. (1988). Principles and Methods of Temperature Measurement (Philo, pg. 3; Fludd, pg. 3-4). Wiley-IEEE.
● Philo of Byzantium – Wikipedia.