Originally Posted By: crs
MMmmm ? Then what is the little button near the L ?


That little "button" near the L is the axle pin for the triggers.

I agree that this a a cocking indicator on the hammer axle pin that points to L for locked (cocked in modern terminology) and D for discharged.

Cocking indicators long ago went away on box lock guns but were retained on many side lock guns in the form of a mark on the hammer axle such as an engraved arrow, gold line (my AyA's), raised ridge (my wife's Grulla) or similar.