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Canadian Engineers Laying Field Telephones

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Running Time
04 min 06 s

Canadian War Records Office, Ministry of Information

This clip shows some of the devices and techniques used in battlefield communications. The first shot of a flagman signalling from a rooftop is followed by a scene of men spooling telephone cable with the help of an upturned bicycle. The next sequence shows signalmen using a truck-drawn cart to lay cable along a road, followed by a shot of two soldiers laying cable in a field and being addressed by an officer. A close-up of a wireless operator is followed by a series of shots of men in a foxhole using telegraph keys and other signalling devices. A second image of a wireless operator, wearing headphones and lying under a culvert shelter, is followed by images of a soldier in a trench speaking on a field telephone. Images of a mobile dovecote are followed by a clip of a document dated August 16, 1918, in which Lt-Gen. Sir Arthur Currie congratulates the troops on their “magnificent success”; then a non-commissioned officer reads the letter to some Canadian soldiers. The conclusion is a close-up of a congratulatory letter from Field-Marshal Sir Douglas Haig. Both letters would have referred to the success of the Canadian troops at the Battle of Amiens, August 8 to 16, 1918.

We view some of the common communication methods used to pass information between command headquarters and the front lines. Telephones were the most effective means, but aboveground cables were easily destroyed by enemy shelling. By the summer of 1916 the process had been accelerated, and an entire battalion could be tasked with laying underground cable and repairing it when damaged. It was still a time-consuming task, however, and the technique of above-ground “laddering” was devised: teams would lay two parallel cables, interconnected with multiple cross-cables. In this way both cables would need to be severed between the same crosspieces in order to cut communications.

Various other methods played their part. Morse code was useful for communication between artillery and observer aircraft. Voice radios were also employed, although they were unwieldy, fragile and could only be used in static situations. In the Battle of Vimy Ridge, Canadians used flags, carrier pigeons, telephone and runners. Wireless telegraphy, still in its experimental stages, was key in the Canadian capture of Hill 70 on August 15.

In the end, it was runners who proved the most reliable and effective means of sending information. During the Battle of the Somme in 1916, commanders relied almost completely upon human messengers to communicate across no-man’s land. Runners would also be essential during the more mobile phases of the war when battlelines shifted frequently. It was hazardous and runners suffered high casualty rates.

Some historians point to the failure of communication systems as one of the contributing factors to the First World War’s terrible casualty rates — unprecedented in the history of warfare. Generals were often misinformed and out of touch with their troops in the battlefield. Acting without the necessary information, they frequently sent men into hopeless situations and failed to seize valuable opportunities.


Signals H.M. Pigeon Service. The Bird Leaving the Trench with a Message, May 1917 Belgian Signal Corps Carrier Pigeon With Code Message

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