What are apportioning scales?
Apportioning scales are special rulers for enlarging patterns from publications explicitly designed to be used with those rulers. (The patterns for one system cannot be accurately enlarged with the scales for a different system; with some, even the same manufacturer’s system of a different date.) The printed patterns have numbers on them. Instead of standard imperial or metric units, the rulers have graded units, smaller units for smaller sizes and larger units for larger ones. You choose the ruler for your size, and enlarge “by the numbers” to get a pattern accurately graded to that size without doing any arithmetic. The systems work for every size from queen-sized to dolls. Apportioning scale systems were originally developed for women who were assumed to be “not good with numbers” (unlike most professional tailoring systems, which required many calculations). Every apportioning scale system had differently sized units and applied them in slightly different ways,
