Possibly one of the most important machines you've never heard of. This is Vaucanson's metal cutting lathe in the Musée des arts et métiers in Paris.

This is credited as the first precision metal cutting lathe. From this device every modern metal cutting lathe can trace its history back. From the prismatic ways, to get carriage, lead screw, and cross slide. Even the interchangeable cutter on the end of the cross slide.

From this lathe, modern precision mechanisation began.