I have just started doing research on the Jemery name.
My grandmother was Blanche (Jemery) Powers. Her father was Julius born 1877 Penacook, NH married to Lillian Chenette. Julius had many brothers.. I have a copy of a Photograph with John, William,Julius,Paul Granpa Francis, Alex and Cousin Herbert La Diew. So the William in my Picture could be the same William you are looking for. I can scan a copy and send it to you.