Naval Technology in 1916-- Part 2: Submarines

6.  Submarine technology.  using breathing gear to escape a sunken sub.

7.  Cargo submarines.  German subs to sneak supplies through the Allied blockade.  Huge subs.

8.  German undersea cargo boat Deutschland, slipped through the British blockade and arrived at Baltimore July 1916.

9.  Anti-torpedo devices.  Whirling plates shot in front of a torpedo to protect cargo ships.

10.  Sea mines.

--DaCoot