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.
Any small piece of steel with a point, similar to that shown in the sketch, will make a good eraser holder. The saving of erasers is nothing compared to the convenience of having a small eraser with a chisel edge or point when delicate erasing is required. It is not clumsy as the usual chunk of rubber with a blunt point, for the person erasing can see what he is doing. I use a leg of an old pair of dividers and cut my erasers in four parts in shapes similar to that shown in the sketch by the dotted lines, and can use them easily until they are about the size of a pea. The friction between the rubber and steel, after the point has been inserted into the rubber, holds the two together nicely. - Contributed by James F. Burke, Lakewood, O.
Ill: A Very Small Eraser can be Held on the Point and Used for Delicate Erasures