Figure 1. Cavendish thermometer. Beginning in 1757 Lord Charles Cavendish,
vice-president of the Royal Society, invented and described a number of thermome
ters utilizing the principle of the dilatation of liquid. One of these was a "
minimum" thermometer used to retain the minimum temperature observed. The liquid
used was alcohol. It was first used by John Phipps on the RACEHORSE in 1773.