In France, by the time of the Battle of Amiens, they were issued the "Woolich" set which used valves (vacuum tubes) which were a great improvement. A bulky interception equipment called a "French Piano" was introduced to pick up any enemy messages. They used a ground loop several hundred yards long with earth pins, a type of I-Toc system. A new amplifier was issued. By the end of the war they had 120-watt wireless sets. (15:00) As German equipment was good Laurie brought some home after the war ended. While his unit was in Cologne as occupation troops he was in Bonn. He refers to postwar articles by Maj. W.A. Steel in the Canadian Defence Quarterly. In Canada he returned to college to become an engineer and gained summer employment as a radio operator aboard steamships on the Great Lakes. (34:00)(Interview 2) In the fall of 1922 he joined the Signal Corps militia as a Lieutenant. After working with the R.C.A.F. on the Manitoba forestry patrol he joined the permanent force Signal Corps in 1923. Radio stations were established in Edmonton, the Yukon, and the North West Territories (45:00) and run by the army for the use of all government departments and, for a fee, civilian traffic was instituted. All messages were sent by key.