Pieces of brass of different thicknesses made letter high, to print with. — M.
They are made in lengths of fourteen inches, but of late years lengths half as long again have been made; one of the edges is bevilled so as to print a fine line, and when a thicker line is required the bottom edge is placed uppermost, which is the full thickness of the brass; by this means lines of different thicknesses are obtained, and also double lines, a thick one and a fine one when required. They are used for column lines in table work; to separate matter that requires to be distinct; and to be placed round pages.
I have found in practice that the best way of forming a good joining at the corners with brass rule, is to cut the rules a little longer than the precise length wanted, and to let one piece project a little at each corner; to push the other piece close up, and, when the form is locked up, then to file the projecting parts away, which makes the corners equal, as shown below.
Wherever two rules join, the end of that which abuts on the other should be cut with a little bevil, so that the upper side should project a little to form a junction with the face of the other; this also prevents the rule binding at bottom.
An ingenious compositor will make many things out of brass rules, such as neat long braces, instead of using middles, corners, and metal rules, which rarely join well, swell rules of different varieties, and many fancy rules, as occasion may require.
In cases where diagrams are required, and there is no engraver within reach, they may be formed by a clever workman, with brass rule. There have been of late years many ingenious and elaborate performances with this article in imitation of architectural drawings of buildings, with pillars, &c.; and I believe no one has displayed more ingenuity and skill in the production of such works than Mr. Ebenezer Parkes, of Fetter Lane.