Originally, crinoline was the name given to a stiff fabric which was used for making ladies' pettitcoats. However, from 1850 onwards, the term cage crinoline was used to describe a rigid steel structure which women wore under the skirts of their dresses to give them shape. This structure was essentially the same as the farthingale which had been used to shape women's clothing in the late 15th, and 16th century.
In a short story entitled 'The Cage at Cranford' (1863), Elizabeth Gaskell writes about the arrival at an English provincial town of a fasionable French crinoline which was mistaken for a parrot's cage!
Click here to see an 1858 steel cage crinoline.