It stopped me cold, because here is a photograph of the handkerchief I bought on ebay a few months ago, which had come from an estate sale in Ohio.
Here they are together.
Here is Mary's own note describing the handkerchief as early 19th century.
It was late, and there were very few people left in the room, but I made each and every one of them come look. The pattern of the handkerchiefs is exactly the same, down to the way the fabric is slightly curved at the corners, though I know of no published patterns this old. A few people whispered, could it be the same one? But no, the photograph shows a rip in the lace where mine is whole. I have read that there was cottage industry in England and Ireland making tatting in the 1800's. I believe the two pieces were made by the same hand, or by the hands of two women in the same village way back then, and one of the pieces found its way to America. Amazing.