Although larger and more powerful than previous British submarines, the J class could not keep up with surface vessels, and operated independently during the war at sea.
Between them, the submarines sank a U-boat, and heavily damaged two battleships, with the loss of J6 to friendly shelling.
Following the war, the six surviving submarines were given to the RAN. All six were paid off during the 1920s. The boats were victims of the worsening economic conditions of the time and the difficulty in maintaining them. The photo shows several of the J class nested alongside HMAS Platypus at Garden Island.
Two were scuttled as breakwaters in Port Phillip Bay, and four were scuttled in the ship graveyard off Port Phillip heads.