This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
A carpenter's wood clamp fastened to the edge of a bench, as shown in the sketch, makes a good substitute for a vise for many kinds of light work. If the clamp is located over or in front of the bench post, holes must be bored in the latter to admit the ends of the clamp screws. A hole is bored through the shoulder screw and a handle attached as shown. - Contributed by H. W. J. Langletz, Harrisburg, Pa.
Ill: The Clamp Attached to a Bench Top will Serve the Purpose of a Vise in Many Instances