In his book, UNDERSTANDING ANTIQUE WINE BOTTLES, Roger Dumbrell provides a notated list of early seals. Unhappily, this particular seal is not listed. He does list some simple "FW" seals, but with no attribution to persons. For example, Dumbrell lists "FW 1764" and "FW" on a circa 1690 onion and "FW" on a circa 1720 mallet. That is my best resource for seal info.