Rules.

The face of the rules ought to be attended to, that they may be of an equal bold, or else tender look, according to the size of the letter or figures with which they are used. Metal rules or dashes, like quadrats, are cast to m’s from the size of one to four, sometimes to six m’s, and are used in schemes of accounts, to direct and connect each article with its summary contents, where they stand opposite, and distant from each other. The same rule may be observed in respect to superior figures, more of the first five being used than the others, except the nullo, which may be used as a degree in geometrical works. Braces are sometimes used horizontally in the margin to cut off a chronological or other series from the proper notes, or marginal references of the work.