This section is from the book "Clothing For Women: Selection, Design, Construction", by Laura I. Baldt. Also available from Amazon: Clothing For Women: Selection, Design, Construction.
These are used on silk or sateen petticoats. Do not allow as much fulness for a bias ruffle as for a straight one; 16 one and one-quarter to one and one-third times the space is sufficient. The bias material itself gives more fulness. Do not cut the selvedge from silk or sateen unless it draws. Cut the bias strips (Bias Cutting, p. 391) as deep as necessary; join in the correct way; stitch hem, being careful in turning the hem to see that the bias is not twisted. Stitch hem and gather ruffles at the top by hand or machine.
These may be cut in one piece, and the decoration placed on the edge and through the flounce, or the flounce may be cut into sections and these joined with entre-deux or lace insertion, and then the flounce trimmed in similar fashion at the lower edge. The circular flounce adds fulness to the edge of the skirt without bulk at the top of the flounce.
Various suggestions for the decoration of ruffles will be found on pages 235, 237, 273, 275, and 284 (Fig. 168).