A 2¼ square film negative. The Type 12 frigate Yarmouth (1959) in No. 2 dry dock in Rosyth Dockyard. A very close view of the bottom of the canoe (lower section) of the dome of Hull Outfit 20 Type 174 sonar on the floor of the dock after removal from its position between 15 and 19 stations. A label noting 'Base of Dome A/S 74' is fixed to the side of the section containing the drain hole. The photographer is on the floor of the dock looking almost directly down into the canoe.