What property of mercury makes it ideal for use in temperature-measuring devices?

Question

What property of mercury makes it ideal for use in temperature-measuring devices?

Answer 1

As someone else below pointed out I went in the wrong direction and was talking barometers. So I am withdrawing this answer.

Answer 2

There is no risk of condensation inside the upper end of the stem.

Answer 3

The fact that it is a liquid and a metal that conducts electrical current makes it good. Such as a thermostat. There is a small tube with mercury and electrical leads in it. When the temperature goes below what is set the tube angles so the mercury completes the circuit by enveloping the electrical leads. Whenthe temperature is what it should be the tuve angles back the other way and the mercury disconnects the leads and the furnace turns off.

Answer 4

Liquid with very low freezing point, high boiling point, and non-zero coefficient of thermal expansion.

(Rich, I can't argue with what you are saying, but we are talking "thermometers" here, not "barometers".)