William H. Rau, American, 1855-1920 William Herman Rau was a Philadelphian with close ties to that city's photographic activities. The son of photographer George Rau, William married Louise Bell, daughter of photographer William Bell. He had worked for Bell until purchasing his father-in-law's company in 1878. Louise Bell Rau later exhibited her own work in pictorialist circles. Among Rau's other