"I was born with a caul, which was advertised for sale, in the newspapers, at the low price if fifteen guineas...I was present myslef, and I remember to have felt quite uncomfortable and confused, at a part of myself being disposed of in that way. The caul was won, I recollect, by an old lady with a hand-basket, who, very reluctantly, produced from it the stipulated five shillings......... ." David Copperfield by Charles Dickens

All credit goes to Betty Smith's A Tree Grows in Brooklyn: "The only notable thing about the birth was that the infant was born with a caul which was supposed to indicate that the child was set apart to do great things in the world" (Smith 78).

Or: We studied the caul in heath class and the superstitions brought with it during a birth.

Hope this helps