Commander, U.S. Naval Forces Operating in European Waters In London, England, with members of his staff, circa mid-1918. Seated in the second row are, from left to right: Captain Dudley W. Knox; Captain Frank H. Schofield; Captain Nathan C. Twining; Vice Admiral William S. Sims; and Captain Harry E. Yarnell. Standing behind and between Sims and Yarnell, with arms folded are, left to right: Commander William Ancrum; and Commander John V. Babcock. U.S. Naval History and Heritage Command Photograph.