Ships Cover for submarines of the E class (1912-1916), H class (1914-1919), K class (1916-1917), L class (1917), L9 class (1918-1919), L50 class (1918-1919), M class (1917-1918), Odin class (1928-1929), Parthian class (1929), R class (1918), Rainbow class (1930), S class (1914), Swordfish class (1931-1933), and Thames class (1932-1934). In addition to the broad classes the following individual submarines are also represented: HMS K26 (1919), HMS Oberon (1926), HMS Porpoise (1932), and HMS X1 (1923). The mix of documents is very eclectic and in some instances quite fragmentary, but general themes which dominate are details of fittings and equipment, vessel & equipment condition reports, details of fuel endurance for all the above classes, proposed alterations, details of relevant experimental work and new developments, and reports on developments overseas with particular emphasis on the US Navy. The earliest document dates from August 1914 and the last from February 1933.