File:Beaufort's Dyke, Cropped From Admiralty Chart No 1577, Published 1913.jpg
This is because it is one of the following:
- It is a photograph taken prior to 1 June 1957; or
- It was published prior to 1974; or
- It is an artistic work other than a photograph or engraving (e.g. a painting) which was created prior to 1974.
HMSO has declared that the expiry of Crown Copyrights applies worldwide (ref: HMSO Email Reply)
More information.