It has been said that there is no place in living history for cotton flannel. However, it was found to be a substitute, along with wool cloth, for carpet in making up hospital slippers. This lead me to search for other mentions in period writings.
My initial search, using Googlebooks, gave me 682 results, of which many will be duplicates. My search covered 1840-1865.
-yards of cotton flannel
-cotton flannel drawers
-Cotton Flannel Undershirt* and Drawers
-Cotton flannel, dyed thus, is also good for common skirts.
-Wide Brown Cotton Flannel
-"Women do wear knitted merino vests in winter to a great extent ; but instead of their cotton, or cotton-flannel drawers, they might advantageously wear the knitted merino drawers worn by men....."
-"Two Pieces of Brown Cotton Flannel. Two Pieces of Bleached Cotton Flannel. These articles received a Silver Medal at the last Exhibition, and still retain the superiority over any similar goods in the present,....."
-"Besides the waistcoat, light flannel drawers should also be worn. These may be made of cotton flannel, which shrinks less, and for this purpose wears better than ordinary woollen flannel."
-"Cotton flannel, which has a thick nap, is an excellent material."
-"Should one be already accustomed to the use of woollen-flannel, she may substitute good cotton-flannel, I think to great advantage. "
-Canton (cotton) flannel
-"Cotton flannel, as it is called, or indeed any sort of cotton, is better and safer for permanent use, next the skin, if we can get along with it without immediate discomfort, than any woollen materials whatever...."
-"The cotton flannel, as it is termed, with its shaggy surface, or nap, ..."
-"A large quantity of cotton cloth and cotton flannel is used to line shoes, and is applied to the surface of the rubber while it is yet in sheets."
-" for those whose skin is too irritable to tolerate a woollen covering the Canton or cotton flannel may be adopted. ..."
This fabric was used as filters in cisterns, to clean glass in telescopes and photography and to make clothing.
I have samples of wool flannel and when comparing it to cotton flannels, it is very similar to cotton diaper flannel.