Student Tasks

Should the Halifax explosion be considered a significant event in Canadian history?

When asking this question, you may want to consider the following criteria for determining historical significance.

• Was the event recognized as being important as it was happening? How notable was the event at the time it was happening?
• How widespread and lasting were the consequences of the event?
• Has the event become symbolic or representative of key historical issues or trends?

Historical Context for Teachers

Port of Halifax in 1917

• During World War I, Halifax, Nova Scotia, was important to the British Empire and its allies as an international port and naval facility. The port of Halifax boasted one of the world’s largest natural ice-free harbours, and was connected by direct railway lines to many North American cities.
• The Royal Canadian Navy’s Atlantic fleet was based in Halifax, and the Canadian Militia kept a large defense force there as well. During the war the Canadian Expeditionary Force (CEF) also used Halifax as the preferred port for sending soldiers to and from Europe.
• Nearly 2000 commercial vessels passed through the port in 1917, not including regular coastal traffic. Collisions were frequent, as ferries, civilian and military shipping vessels, and small fishing and pleasure crafts all fought for space in the harbour.
• Local pilots from Halifax and other nearby communities were used to guide the ships through the Halifax harbour because they were more familiar with the local geography.

Causes of the explosion

• At 7:30 a.m. on December 6, 1917, a French munitions ship, the Mont-Blanc, left its anchorage outside the submarine nets at McNab’s Island (an island at the mouth of the harbour) and headed into The Narrows (a small passage leading from the Atlantic into the harbour itself) at a speed of four knots, well within the five-knot speed limit for traffic in the harbour. It was carrying a highly explosive mixture of 2300 tons of wet and dry picric acid, 200 tons of TNT, 10 tons of gun cotton and 35 tons of benzol (oil).
• As the Mont-Blanc entered The Narrows, the crew of the Belgian relief ship Imo raised anchor and began leaving Bedford Basin (the largest part of the harbour). After travelling slowly through the crowded basin, it picked up speed as it neared The Narrows, reaching a speed of seven knots.
• As the Imo entered The Narrows, an American steamer passing by warned William Hayes, the pilot of the Imo that another ship was coming along the narrow passage.
• The Imo was three quarters of a mile from the Mont-Blanc when Francis Mackey, the pilot of the Mont-Blanc, first spotted it. Mackey noticed that the Imo was moving very quickly and was on a path that would cut across the bow (front) of the Mont-Blanc. Mackey blasted the steam whistle to indicate that the Imo was in their shipping lane.
• Hayes responded with two blasts, indicating that the Imo would be continuing on its present course. Mackey sent a second blast as the Mont-Blanc moved slowly along the Dartmouth Shore. Hayes responded again with two blasts indicating that the Imo would not change course.
• As the two ships headed directly for one another, both took action to avoid a collision. The Mont-Blanc turned hard to port (left), while the Imo reversed its engines and turned strongly starboard (right). Unfortunately, because both ships turned in the same direction, the two moves cancelled each other and the Imo’s bow sliced deeply into the Mont-Blanc’s starboard (right) side.
• While the damage to the Mont-Blanc was not particularly severe, the impact toppled barrels of benzol (oil) that broke open and flooded the deck . Sparks from the collision lit the oil on fire and thick black smoke appeared from the front of the Mont-Blanc.
• Le Medec, the ship’s captain, decided to abandon ship because he thought the fire was too volatile to contain, and because heat and smoke prevented the ship’s pumping apparatus from working properly. Two rowboats containing the 40-man crew reached safety on the Dartmouth side of the harbour as the burning ship drifted toward the Halifax shore.
• The Mont-Blanc drifted up to Pier 6, and the fire spread from the ship to the pier's wooden frame. Just after 9:00 a.m., the Mont-Blanc exploded with a blast equivalent to 2.4 million kilograms of explosives. The explosion was the most powerful man-made explosion ever recorded until the dropping of the atomic bombs in 1945.

Consequences of the explosion

• For almost two square kilometers around Pier 6, nothing was left standing. The blast and shockwaves flattened much of the Halifax shoreline, including the railway terminals, dry dock facilities, the Richmond neighbourhood and the Acadia Sugar Refinery. On the Dartmouth side of the harbour, Tuft's Cove took the worst of the blast and Turtle Grove, the small Mi'kmaq settlement, was completely destroyed.
• The explosion pushed the Imo aground on the Dartmouth shore, shattered the upper parts of the ship and killed many of its crew. Any ships in the harbour that were close to the explosion suffered heavy damage and casualties. The Royal Canadian Navy cruiser the HMCS Niobe was destroyed and the bodies of the six-man crew were never found.
• The heat and pressure caused by the blast created a fireball of hot gases, soot, unburned coal, carbon from explosives and shrapnel high above the harbour. As the gases cooled, a giant cloud formed and the soot, carbon and shrapnel fell in a deadly shower. Fragments of the ship were found as far as 3.5 miles from the explosion site.
• Water around the Mont-Blanc was vaporized by the heat, and the explosion created a 16-meter tidal wave that pushed three city blocks into the Richmond neighbourhood, hitting people as they moved toward shelter or escaped from boats.
• The blast killed more than 1600 people and wounded nearly six times that number. It destroyed 1500 homes and severely damaged another 12 000, leaving 20 000 people homeless. The majority of deaths and injuries resulted from people being too close to windows as they shattered or trapped in burning buildings that were ignited by tipped coal stoves and broken gas lines.
• Military troops immediately spearheaded rescue efforts and city officials were quick to organize volunteer relief committees to provide medical treatment, food, supplies and shelter. When hospitals became overcrowded, some injured or homeless were taken to hospitals in nearby cities and towns.
• On January 22, 1918, the Federal Government created the Halifax Relief Commission (HRC) to handle pensions, claims for loss and damage, rehousing and rehabilitation for victims of the explosion. The HRC administered $30 million dollars that was donated by the government, industry and individuals worldwide.
• Help also poured in from all over Canada and other parts of the world. Boston, the closest American city, sent a train loaded with supplies, medical personnel and volunteers. Even today, the city of Nova Scotia sends a Christmas tree to Boston each year as recognition of the help provided in their time of need.
• An official enquiry was launched a week after the explosion and was the source of much study. The captain and pilot of the Mont-Blanc were initially blamed for causing the disaster; however, the case was quickly appealed to the Supreme Court, where it was decided that both ships were equally at fault.

Map of the Halifax explosion

The image above shows the movements of the ships involved in the collision, along with the furthest reach of the tsunami that followed the explosion.

 © Laura M. MacDonald (2005), Walker Books, an imprint of Bloomsbury Publishing Plc.