O
Odontograph (ō-dŏn′-to-grăf). An instrument employed in making or drawing gear-wheel teeth.
Oliver. A foot-power hammer used by blacksmiths, mainly for forging bolts or studs.
Outside-calipers. Calipers used to measure external surfaces.
P
Panelling-machine. A machine for cutting mouldings upon panels.
Parallel-file. A file whose thickness is equal from end to end.
Parallel-vise. A vise in which the gripping face of the movable jaw is maintained parallel to that of the fixed jaw.
Paring-chisel. A wood-worker’s chisel that is pushed to its cut by hand pressure.
Pattern-lathe. A lathe designed for the use of pattern-makers.