What is the celsius scale temperature based on

Celsius, also called centigrade, scale based on 0° for the freezing point of water and 100° for the boiling point of water. Invented in 1742 by the Swedish astronomer Andres Celsius, it is sometimes called the centigrade scale because of the 100-degree interval between the defined points.

Explanation:

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.