History of the Thermometer By austinbally2014 Oct 19, 1593 Galileo's Thermoscope Apr 8, 1612 Mouth Thermometer Jun 15, 1612 Santorio Thermoscope Jul 4, 1654 Ferdinand II Thermometer May 19, 1714 Fahrenheit Thermometer Apr 16, 1724 Fahrenheit Scale Nov 30, 1742 Celsius Scale Mar 23, 1848 Kelvin Scale May 7, 1867 First Medical Use of Thermometer Jul 29, 1984 Ear Thermometer