Beam compass
Beam compass, metal frame marked "HO ^ 8", length of frame 2' 6 1/2",width 4", arm divided on silver to 1/20", reading by vernier to 1/1000", clamp and screw motion, with screw adjustment for pencil
Beam compass, metal frame marked "HO ^ 8", length of frame 2' 6 1/2",width 4", arm divided on silver to 1/20", reading by vernier to 1/1000", clamp and screw motion, with screw adjustment for pencil