Early 1900s vintage double sided flannel (brushed on both sides of the cloth), very heavy all cotton fabric, natural undyed, unbleached color. This was meant for use for bed linens and quilts, warm winter nightclothes and petticoats, jackets and gowns for babies and small children.
It's 56" wide, this piece is 2 1/2 yards. It's never been laundered, and has a very obvious spot of storage soil (shown in the second photo), as well as a little browning and foxing from age. We've left it just as found, but you'll probably want to wash and / or soak this before you begin sewing. (A good idea anyway, since we're thinking this would proabably shrink a little in washing, older flannels so often do!)