A Charriere tri-valve vaginal speculum, sometimes referred to as a Segala type speculum. The three blades collapse to form an oval shape which accommodates the obturator. The speculum would be inserted in this form, then pressure applied to the  handles would expand the blades enough to remove the obturator and the hinged blades would be further extended into a circular configuration and locked in place. Signed Luer. The speculum is made from ebony with an ivory insert in the handle. Mid to late 19th Century.