• The mercury thermometer is designed to measure the temperature of the human body; graduated to cover a range a few degrees on either side of the normal body temperature The thermometer consists of mercury contained in a bulb at the bottom of a graduated sealed glass capillary tube marked in degrees Celsius or Fahrenheit.
Lab thermometer developed during the 16th and 17th centuries, athermometer (from the Greek (thermo) meaning "warm" and meter,"to measure") is a device that measures temperature ortemperature gradient using a variety of different principles. Athermometer has two important elements: the temperature sensor(e.g. the bulb on a mercury thermometer) in which some physicalchange occurs with temperature, plus some means of converting thisphysical change into a numerical value (e.g. the scale on a mercurythermometer).
Sixs maximum and minimum thermometer is a popular thermometeramong gardeners for use in greenhouses. Its purpose is to read themaximum and minimum temperatures reached since thethermometer was last read. Generally speaking a minimumtemperature occurs during the night and a maximum during the day. Itwas invented by James Six towards the end of the eighteenth century,and consists of a fairly large cylindrical bulb full of alcohol, connectedby a U- shaped stem to a second bulb nearly full of alcohol or oil ofcreosote.
This digital thermometer circuit diagram uses a common1N4148 diode as the temperature sensor. The temperaturefactor of the diode, -2 mV / 0C is exploited for this applicationto create an accurate electronic thermometer. To display themeasured temperature, a digital multimeter is used and so wecan measure temperature values from -9.990C up to +99.90C.