Metal Rules

Straight lines cast on pieces of metal similar to quadrats, but higher; they are rarely cast to founts larger than English. They are used as leaders; to cut off sums of money from the line which contains the sum total; for transverse lines in columns; sometimes for column rules, but very seldom; and for blanks, where the names of persons, &c., are omitted; em metal rules are sometimes used for divisions in a paragraph instead of a point. They are generally of one em, two ems, three ems, and four ems, but in English founts their size does not exceed three ems; sometimes there are en metal rules cast. Metal rules ought to be cast exactly on the middle of the body, and be continued precisely to the sides, so as to join each other at the ends, even if they are placed alternately with the sides reversed; should this not be the case, the continuity of the line must be broken, and it will necessarily have a disagreeable appearance.