The History of the Body Temperature Thermometer

According to Wikipedia, the Free Encyclopedia. "The thermometer was not a single invention but a development." The historical development of the body temperature thermometer goes back to the invention of the thermoscope which was invented by Avicennia in the 11th century and further developed by Galilio Galilei with several other European scientists in the 16th and 17^th century. They included names such as, Cornelius Drebbel, Robert Fludd and Santorio Santorio, Philo and Hero of Alexandria and Guiseppe Biancani.

The secret of how their principle work is that certain substances notably air, expand and contract. Philo and Hero of Alexandria described a demonstration of a closed tube partially filled with air, had its end in a container of water. Expansion and contraction of the air changed the position of the water and air interface along the tube. This was the development of the Thermoscope. The Thermoscope differs from the thermometer in that it did not have a scale of measurement. Santorio Santorio was the first person to put a scale on the Thermoscope. He was also the first person to use a thermometer to measure body temperature in a scientific way in 1612.

The flaw with these early thermometers was that they were sensitive to air pressure. Many names came along that tried to perfect the thermometer over the years.

In 1654 Ferdinando 11 de' Medici, " The Grand Duke of Tuscany" devised a scaled tube filled with alcohol, a bulb and a stem. They were depending on the expansion of a liquid and independent of air pressure. These thermometers had no standard scale of measurement or gauge.

In 1665 Christian Huygens had a brilliant idea to use the melting and boiling points of water as a standard gauge. Other names joined the development in perfecting the measurement and efficiency of the thermometers.

In 1694 there was Carlo Renaldini who proposed a fixed point on a universal scale.

In 1701 Isaac Newton proposed a scale by 12 degrees between the melting point of ice and body temperature.

In 1724 Daniel Gabriel Fahrenheit manufactured thermometers using mercury which provided more efficient readings.