Farmhouse BatterySwansea, UK
Farmhouse Battery was built on Flat Holm Island during the 1860s and mounted two 7-inch RML gun on a Moncrief Disappearing Mounts.
The A gun was mounted in a pit with an open rear. During World War 2 the pit was covered in and the pit used for a generator.
The B gun was in an enclosed pit with a short tunnel entrance.
Part of both the 7-inch guns lies on the top of the battery.
A contemporary diagram of a disappearing mounts used on Flat Holm can be see here.