… Horsehair in French. Use of the word “crinoline” in describing the new 1840’s undergarments suggested that horsehair was used to give it stiff shape.
At first horsehair was used in a strip as a lining hem, and then at the top of a sleeve to keep its shape.
(Left: horsehair petticoat 1850; Right: early crinoline hoop 1852)