Letter from J D Griffith Davies, Assistant Secretary of the Royal Society on a paper 'On the salinity of the surface waters of the Irish Sea' by Joseph Proudman to the Hydrographer to the Navy, the Admiralty Encloses the paper. It may contain information that could be of use to the enemy. If he considers it to do so, publication can be deferred until after the war. A restricted confidential edition could be printed for use by the government instead. [Published in Philosophical Transactions A, 1946]. 5 December 1940