The following definitions for “ruler” are taken from Ballantine’s Law Dictionary (3rd edition) and Webster’s Dictionary (1828):
(Ballantine’s)
A strip of wood or metal, having a straight edge, marked in inches and fractions of inches, and used in drawing a straight line and in measuring length.
A king, queen, or other sovereign.
(Webster’s)
RU’LER, n.
1. One that governs, whether emperor, king, pope or governor; any one that exercises supreme power over others.
2. One that makes or executes laws in a limited or free government. Thus legislators and magistrates are called rulers.
3. A rule; an instrument of wood or metal with straight edges or sides, by which lines are drawn on paper, parchment or other substance. When a ruler has the lines of chords, tangents, sines, &c. it is called a plane scale.
The Last Bastille 