To check our underfloor heating something appealing Simple was needed; without electronics and gadgets. Galileo's invention was just right. Well packed in Styrofoam peanuts hit a good piece. Setting up, watch and wait what happens ... After a few days I had the hang of it. Contrary to the description stated not lower the upper balls but the top of the lower temperature. Mathematicians speak - I think - of supremum and infimum, or vice versa. But the balls in thermometers were not kind enough to tell by independent mounting, dismounting the temperature. No, the thermometer had only shaken (not stirred!) Are. Then the decisive ball up or down moved. In short, the thermometer will be treated kindly, otherwise it does not tell the temperature; but then only with +/- 1 degree deviation. To return I was too lazy. Also, I've gotten used to 'his' or 'her' whims.
