A cervical speculum used to dilate the os cervix. Turning the screw retracts a central rod which is T-shaped in its distal part and so separates the blades of the speculum. Dating to the mid 19th century this is of French origin and is signed "Collin" on the stem, who was a renowned maker of quality medical instrument in Paris. The octagonal handle is made from ebony, the shaft is made from polished steel and the blades of the speculum and the screw nut on the handle are made from German silver.