This appears to be a very early single-comb movement, the hallmark date of the case being only four years after the traditionally accepted date of Francois Lecoultre's invention of the one-piece comb. It is held in place by four irregularly-spaced screws. The right-hand end-cap of the cylinder has a notched rim; alternate notches are extended with scribed lines on the face, numbered from O to 48. Presumably, this is a form of rigid rotation