A 1792 guillotine model
The 1792 model.
This is as close as we can get to the original revolutionary guillotine from 1792.

The 1792 model

Compare the 1792 and the 1870 guillotine

The Guillotine has changed since it's first appearance in 1792. And the model shown here is my guess of how it may have looked. The original machine is not preserved, but there are guillotines in museums in Belgium and the Netherlands, that looks a bit like this one. The correct time for the guillotine in the Netherlands is between 1795 and 1800. The one in Belgium is younger, approx 1830.

The major improvements were made in 1870-72, when Leon Berger (an executioner's assistant) changed the design of the guillotine to its final form. The guillotine became more mobile and easier to mount.

New features were added, but the principle and the effect remained the same.

In 1792 the guillotine was made of red painted wood. A simple device on the side was used to maintain the blade/mouton in position, and to release it. The rope followed the mouton down.

The wooden grooves were very soon lined with brass or iron, to prevent the wood from swelling, which could interfere with the movement of the mouton. And the rope was no longer following the mouton down, which gave the mouton more speed.

In 1870 the vertical posts were supported by metal braces, insted of the wooden ones used on earlier models.

The mouton was driving in the grooves on four wheels, two in each groove. On top it was held in place by an ingenious contraption, consisting of an arrow headed spike and a sprung-grab. The jaws of the sprung-grab were opened by means of a handle on the post.

When the mouton was in position the rope was pulled of the hook by means of a thin rope. To stop the falling mouton, a spring-system was placed in the lower end of the groove

The lunette had a copper facing towards the side of the blade, and a new lock/release mechanism was implemented.

A 1870 guillotine model
The 1870 model.
This is the improved model from 1870, which was used until 1977.

The 1870 model
A 1792 guillotine model

1792
A simple device on the side was used to maintain the blade/mouton in position.
A 1870 model

1792
The vertical posts were supported by wooden braces.
A 1792 guillotine model

1792
The lunette was operated manually.
Blade falling on a 1870 guillotine model

1870
The mouton was held in place by a contraption, consisting of an arrow headed spike and a sprung-grab.
Mouton with blade 1870 guillotine

1870
The mouton was running on four wheels, two in each groove.
Lunette of the 1870 guillotine

1870
The lunette was released pushing a handle. The mouton was released pulling down the déclic handle above.
nothing

The official machines always had an oblique blade, but other shapes were used one guillotines homemade in the provinces, when the official guillotine was a long time comming in 1792.