John Roderick
McDougall

Most men who served in the Canadian Expeditionary Force (CEF) in the First World War served in the infantry (foot soldiers) or artillery (weapons). Others served in various support units, including engineers, labour battalions, ammunition columns, service units, as well as doctors and nursing sisters in the Canadian Army Medical Corps. A small number also served in tunnelling companies, which were attached to the Royal Canadian Engineers.

The onset of static trench warfare in the autumn of 1914 created a need for new tactics in the battlefields of the Western Front. Beneath the surface, underground tunnels were dug by both the Allies and the Central Powers below enemy positions to destroy their defences and advance their offences. Northeastern France and western Belgium, where much of the fighting took place, was already a major coal-mining region, and its soil conditions were ideal for mining. By early 1915 both sides were mining and counter-mining intensively.

Men employed in tunnelling companies (called tunnellers or sappers) often performed difficult, dangerous, and highly-skilled work. Experienced miners from Australia, Britain, Canada, and New Zealand were recruited to fight this subterranean war, their efforts largely overlooked but still etched in the landscape today. Of the hundreds of Canadian men who served in this role, approximately 200 were from Cape Breton. John Roderick McDougall of Donkin was one.

The CEF established four tunnelling companies during the war, three of which served in France: No. 1 was organized in September 1915 and recruited miners already serving overseas in infantry battalions, supplemented by men recruited in mining communities in eastern Canada; No. 2 was also organized in September 1915 and recruited in mining communities in Alberta and British Columbia; No. 3 was organized at Bailleul, France, in December 1915 and was formed by absorbing the brigade mining sections of the 1st and 2nd Canadian Divisions. No. 4 Canadian Tunnelling Company was organized in March 1916 and recruited miners in western Canada. It did not go to France, but remained in England as a reserve unit to provide reinforcements to the other companies.

Tunnelling was extremely dangerous work that involved heavy labour and required the knowledge and expertise of men who could cope with the psychological effects of working underground. As a result, almost all tunnellers were recruited from mining communities. Although precise figures are not known, as many as 1,100 men may have served in the Canadian tunnelling companies.

Tunnelling companies dug tunnels where explosives were placed, but they also constructed subways, cable trenches, saps and underground chambers for signal or medical services. In suitable locations, extensive networks of tunnels were dug behind the front lines, allowing for the movement of men and supplies into the front trenches without enemy detection.

Tunnellers worked in extremely difficult conditions underground, in cold, dark, wet, poorly ventilated and confined spaces. Digging was done by candlelight and in near silence to prevent any chance of revealing their location to the Germans. Careful listening, often using geophones (acoustic detection device) was also required to detect enemy activity and movement.

Subterranean warfare was extremely dangerous, because explosions, flooding, and collapses posed a daily threat. Unexpected encounters with German tunnellers (called Pionere) were also possible, and many men lived in fear of sudden death from asphyxiation, drowning, entombment, and explosions.

Mines tunnelled under enemy lines played a key role in several battles. On March 27, 1916, six mines were detonated under German positions close to Messines, near Ypres, Belgium. The largest was dug by No 1 Canadian Tunnelling Company at St Eloi and involved 43,400 kg of explosives. The resulting explosion initiated the Battle of St Eloi, one of the more chaotic battles of the war, in which the 25th Battalion (Nova Scotia Rifles) fought its first battle.

The Somme offensive, one of the most brutal and bloody of the war, also began with the explosion of mines. On the morning of July 1, 1916, several explosive charges laid by British tunnellers were detonated beneath German positions along the Hawthorn Ridge, near Beaumont Hamel. The attack that followed was a catastrophic loss for the Allies in which the 1st Newfoundland Regiment was nearly decimated.

In preparation for the Battle of Vimy Ridge, tunnelling companies dug an astonishing 20 kilometres of subways for foot traffic, tramways equipped with rails for moving ammunition to the front lines and evacuating wounded soldiers, and light railways—all concealed from the Germans. The tunnelling network at Vimy Ridge housed 24,000 men prior to the attack (April 9, 1917) and was equipped with electric lighting, kitchens, latrines and a medical centre. A 250-metre section has been preserved and is accessible to the public, in recognition of the pivotal role which the tunnelling companies played in the Canadian victory at Vimy Ridge.

In the months leading up to the Battle of Messines, Allied tunnellers laid 25 massive mines charged with several hundred thousand kilograms of explosives under the German-occupied Messines ridge. They were detonated on the morning of June 7, 1917, resulting in an enormous explosion that killed 10,000 German soldiers. The 1st and 3rd Canadian Tunnelling Companies were involved in the preparation for and execution of the explosion, including electrician turned Sergeant Daniel “Danny” Lynk of Glace Bay, who was awarded the Military Medal for his actions during the battle.

Following the summer of 1917, the war became more mobile and underground warfare diminished. Tunnelling personnel were assigned to other engineering or infantry units, while some continued to work on underground subways and shelters for frontline infantry. During the German offensive in the spring of 1918, several tunnelling units were called upon to serve as infantry. When that offensive failed and the Allies began their final push against the Germans, tunnelling companies worked to make safe captured towns, villages and facilities, including the very dangerous work of clearing tunnels of the many enemy explosives left behind.