I
Idle pulley or guide pulley. A pulley employed to guide a belt.
Independent chuck. A chuck in which each jaw is operated separately.
Index-plate. A plate having holes or notches accurately dividing a circle into equal divisions.
Inserted-tooth cutter. A cutter in which the teeth are inserted in a disc or head.
Inside calipers. Calipers used to measure inside dimensions, as boxes, recesses, etc.
Intermediates. The wheels that are between the front driver and last follower of a train of gear wheels.
Involute. A curve generated by the path of a given point in a straight line, as the line is rolled upon a circle. ([Vol. I. p. 31].)
J
Jack-plane. A plane employed to rough out the work.