British E class submarine

The Royal Navy's E-class of diesel/electric submarines were built between 1912 and 1916 and were the mainstay of the submarine fleet during the First World War. A total of 58 boats were built, including two constructed for the Royal Australian Navy.The boats were built in three groups. Six boats of Group 3 were built as minelayers which were fitted with 20 vertical tubes instead of the two beam tubes.
See more at Wikipedia.org...