And today? Digital thermometers with minimum and maximum, two sensors for inside and outside, showing tenths of a degree, a switch can choose centigrades or Fahrenheit and for a cheap money you can obtain them in a junk store! Do you know how they work? Opened them and inspected?? Touched, understood???

A Digital Thermometer inside - insight?
But how do they work? Pupils may ask you, perhaps only to bamboozle you as they can be sure of your ignorance... and - if, thanks to your special knowledge, you know it - what will you say?

move on