David Cohen was a Watchmaker listed as living in Mather Street Great Bolton in 1891 with his wife Sarah. A David Cohen was listed in the 1881 Prestwich census as an Apprentice Watchmaker, at 25 Clarence St, and so this may be the same person. it appears that he moved to London Road, Alderley Edge with his family at the turn of the Century, where he established his business.
There are no known examples of his work from his time in Bolton.