A thermometer is an instrument which is used for measuring temperature. It measures how cold or hot something is. There are a number of different types of thermometers. The most common type of thermometer is usually made up of a small, hollow glass tube. At the bottom of the tube is a bulb, which holds a liquid such as mercury. When there is an increase in heat, the liquid inside the bulb expands, pushing up into the tube. Another type is a digital thermometer, which uses electronics to measure temperature. The first recorded thermometer was invented by Santorio Santorio, an Italian, in the sixteenth century.
What is a Thermometer?
