This is the earliest Bausch & Lomb instrument in the collection. The tripod base supports a round pillar and round limb, attached by a compass joint. The body-tube with a triple nosepiece moves by rackwork, and the fine adjustment is by the screw on the top of the limb. Below the round stage are the swinging condenser and double mirror. It comes with a wooden carrying case and accessories. Signed: Bausch & Lomb Optical Co.