Pierced for binder.
'This chapter supersedes the whole of Chapter X and parts of Chapter XVII of the "Admiralty manual of Hydrographic Surveying" (1948 Edition)' - title page verso.
Admiralty manual of hydrographic surveying. Vol.2: Chapter 3, Sounding. Published by Hydrographer of the Navy in 1969. Publication and catalogue information, links to buy online and reader comments.