The device was perfected - though not invented- by Doctor Joseph Ignace Guillotin (1738 - 1814). The 'e' at the end of the noun is a later, British, addition.
Ironically, he belonged to a movement seeking to abolish capital punishment altogether. Guillotine-like implements were used on delinquents from the nobility in Germany, Italy, Scotland and Persia long before the good doctor's era. Guillotin and German engineer and harpsichord maker, Tobias Schmidt, improved and industrialized it.
It was Schmidt who transformed the blade, changing it from round to the familiar form and placing it at an oblique, 45 degree, angle. The process of severing the head - the blade falling, cutting through the tissues and severing the head - took less than half a second. More than 40,000 people were guillotined during the French Revolution and in its immediate aftermath (1789-1795).
Nor was the guillotine abandoned after the French Revolution. As late as 1870, one Leon Berger, an assistant executioner and carpenter, added a spring system, which stopped the mouton at the bottom of the groves, a lock/blocking device at the lunette and a new release mechanism for the blade.
The murderer Hamida Djandoubi was beheaded on September 10, 1977, in Marseilles, France. The guillotine was never used since.
a.. Total weight of a Guillotine is about 580 kg
b.. The guillotine blade with weight is over 40 kg
c.. The heights of the guillotine posts average about 4 meters
d.. The guillotine blade drop is about 2.3 meters
e.. The falling blades rate of speed is about 7 meters/second
f.. The actual beheading was completed in 2/100 of a second
g.. The power when the guillotine blade stops at the bottom is 400 kg/square inch