A 2¼ square film negative. The Type 12 frigate Yarmouth (1959) in a dry dock in Portsmouth Dockyard. A general view of five 'C' sentry anodes in a row on the bilge keel between stations 59 and 61 on the starboard side, taken from the bottom of the dock. A man wearing a safety helmet, duffle coat and wellington boots is standing on the dock floor holding a scaled description board up to the bilge keel.