Halifax explosion

On the morning of 6 December 1917, in the harbour of Halifax (PL) in the Canadian province of Nova Scotia, two ships collided: the French freighter Mont-Blanc, loaded with explosives, and the Norwegian Imo. A fire broke out on Mont-Blanc, and at about 9.04 a.m. the whole cargo exploded. The blast levelled the Richmond district in the northern part of the city, badly damaged Dartmouth on the other side of the harbour and killed, according to various counts, from about 1,800 to nearly 2,000 people. About 9,000 were injured. Until the first nuclear explosions it was regarded as the largest man-made explosion. It is also considered the most tragic disaster in Canadian history.

A wartime port

During the war Halifax was one of the most important ports on the western side of the Atlantic. From here transports of Canadian soldiers sailed for Europe, hospital ships with the wounded returned here, and from 1917 merchant ships gathered in Bedford Basin, protected by two lines of anti-submarine nets, before setting out in convoys to Britain and France. Every neutral ship bound for North American ports had to call at Halifax for inspection. The population of the city and Dartmouth grew to about 60,000–65,000. Before the war ships with dangerous cargoes were not allowed into the harbour, but the U-boat threat led to the rules being relaxed.

Imo, chartered by the Commission for Relief in Belgium, was sailing empty to New York for supplies for the population of occupied Belgium. She had arrived in Halifax on 3 December for inspection and on 5 December was given clearance to put to sea, but she was delayed taking on coal and did not make it before the nets were closed for the night. Mont-Blanc, under Captain Aimé Le Médec, arrived from New York on the evening of 5 December and was to join a convoy for Bordeaux in Bedford Basin. According to the most commonly cited figures, she carried more than two thousand tons of picric acid, more than two hundred tons of TNT, several dozen tons of nitrocellulose and drums of highly flammable benzol stacked on deck.

Collision in the Narrows

On the morning of 6 December both ships got under way almost at the same time. Imo was signalled to leave Bedford Basin at about 7.30 a.m. and quickly, at a speed exceeding that allowed in the harbour, entered the Narrows, the strait linking the basin with the outer harbour. Passing other vessels, she moved over to the wrong, eastern side of the channel, on which Mont-Blanc was sailing. The French ship’s pilot, Francis Mackey, signalled that he had right of way, but Imo replied that she would not give way. At the last moment Mont-Blanc turned to port and Imo went full astern. At about 8.45 a.m. the Norwegian ship’s bow struck Mont-Blanc’s starboard side. The damage was not serious, but the drums of benzol toppled over and burst, and sparks as the hulls separated ignited its vapour.

Mont-Blanc’s crew knew what she was carrying. The captain ordered the ship abandoned, and the sailors rowed in two lifeboats towards Dartmouth, shouting warnings to other vessels in vain. The burning ship drifted towards the Richmond waterfront and grounded at Pier 6. Onlookers drawn by the spectacular fire gathered on the shore and at the windows of houses. The tug Stella Maris and boats from the British cruiser Highflyer and the Canadian Niobe came alongside and tried to pull her away from the pier. The fire brigade also raced to the harbour with the first motorised fire engine in Canada. The railway dispatcher Vince Coleman, working just over 200 metres from the waterfront, returned to his post and telegraphed a warning to incoming trains to stop before the city. He was killed at his key.

The blast

At about 9.04 a.m. Mont-Blanc’s cargo exploded. The ship was blown to pieces, and the shock wave destroyed or damaged buildings within a radius of more than two and a half kilometres. Fragments of the hull rained down on Halifax and Dartmouth, and part of an anchor was found several kilometres from the harbour. A cloud of smoke rose several kilometres into the air, and the explosion was felt even on Prince Edward Island and Cape Breton, more than 150 kilometres from the city. A tsunami threw Imo ashore on the Dartmouth side and washed away the Mi’kmaq settlement on Tufts Cove. One man of Mont-Blanc’s crew was killed, but few of the people who had tried to fight the fire survived.

Most of the victims died on the spot: under the rubble of a sugar refinery, a cotton mill, railway workshops and houses. Hundreds of people who had been watching the fire from behind windowpanes were blinded by shards of glass. Overturned stoves and lamps started fires that consumed whole blocks of wooden buildings in the North End. At first many residents believed the city had been bombed by the Germans. The army manned the batteries, then threw all its strength into the rescue effort. Soon panic broke out because of a fire near the magazine at the Wellington Barracks. People fled their homes for fear of a second explosion until, at about noon, it became clear that the danger had passed.

Rescue and blizzard

The injured were taken to hospitals in anything that had wheels. The new Camp Hill military hospital admitted about 1,400 casualties on the first day. Rescuers came ashore from the British warships in the harbour, and in the course of the day they were joined by Americans from the cruiser Tacoma and from other vessels passing nearby. At about noon the province’s lieutenant governor convened a citizens’ committee, from which the Halifax Relief Commission emerged. By the evening more than a dozen relief trains had arrived from Nova Scotia and New Brunswick, with doctors, nurses and supplies. During the night a train with aid organised by the authorities of Massachusetts set out from Boston.

The next day, 7 December, a violent blizzard struck the city. It buried the ruins under about 40 centimetres of snow, stranded the relief trains and once again brought down the telegraph lines. The search for survivors had to be halted, but the snow helped to put out the fires. The Boston train reached Halifax only on the morning of 8 December, and its doctors relieved the exhausted hospital staff. A year later the grateful city sent Boston a Christmas tree. Since 1971 Nova Scotia has sent a tree there every year, which stands as the city’s official Christmas tree on Boston Common.

Victims and damage

The exact number of dead was never established. The official book of remembrance of the Nova Scotia Archives lists 1,782 victims, while other counts give about 2,000. The injured amounted to more than a tenth of the population. Eye surgeons had to remove about 250 destroyed eyeballs, which made the city an important centre of care for the blind. About 1,600 houses were destroyed and 12,000 damaged. About 6,000 people were left homeless, and about 25,000 had no adequate shelter in the middle of the Canadian winter. The material damage was estimated at about 35 million Canadian dollars. About 30 million was raised in aid, most of it from the federal government and more than 4 million from the British government.

The port, though damaged, was soon back at work. A convoy left Halifax as early as 11 December, and the naval dockyard resumed work before Christmas. Prime Minister Robert Borden, who was himself a member of parliament for Halifax, gave assurances that the rebuilding of the port was of the highest importance to the whole Empire. In the Halifax constituency there was not even a vote in the election of 17 December, because only two government candidates had been nominated for the two seats.

Inquiry

Soon after the explosion the authorities detained most of the Germans in the city, and the helmsman of Imo was arrested as an alleged spy because he was carrying a letter in a language taken for German. It turned out to be written in Norwegian. On 13 December an inquiry into the causes of the collision opened before Justice Arthur Drysdale. Its findings, published in February 1918, put the blame on the captain and pilot of Mont-Blanc and on the Canadian officer responsible for harbour traffic. None of them, however, was convicted. In civil proceedings the higher courts, including in 1920 the Judicial Committee of the Privy Council in London, ruled that both ships were equally to blame for the collision.