I've been reading College Girls by Lynn Peril, and there's a chapter called "Fit in Mind and Body." One page describes the ideal shape of a female student in 1912, according to Dr. Dudley A. Sargent, an early advocate of physical education. He was the director of the Harvard gym from 1879 to 1919. Some of the ideal measurements are:
Weight: 118 lb
Height, standing: 61 3/4"
Height, sitting: 33 1/2"
Girth of Chest: 31 1/2"
Girth of Chest, full: 33 1/2"
Waist: 23 1/4"
Hips: 35 1/4"
Girth of thigh Thigh: 21" each
The measurements look like what we would call a size 0 or 2 in 2007 terms. However, it's really unlikely that a girl with these measurements would weigh 118 lb, even if she was really athletic and muscular. These measurements look like someone who is around 100 lb, give or take. 108 lb would be stretching it a little, I think.
According to Ms. Peril's book, these measurements were found in the March 1912 edition of the Ladies Home Journal.
Credit:
Lynn Peril, College Girls: Bluestockings, Sex Kittens, and Coeds, Then and Now, (New York: W.W. & Norton Company), 2005. 263