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Chief Master Sergeant
Dec 20, 2003
Ipswich, Suffolk
This is a incident not much known about these days but until the first atomic bomb test in 1945 it was the largest man made explosion in history

At 9:05 on the 6th December 1917, a munition ship exploded in Halifax harbour, (Nova Scotia, Canada). This explosion was so vast that it killed over 2,000 people and completely flattened two square kilometres of northern Halifax.
The war in Europe demanded and consumed vast amounts of people and materials from the new world. Halifax is a deep natural harbour, which was ice-free. since the 1812 war, the harbour was defended by a series of forts, Halifax was now a garrison town, as well as a naval dockyard and harbour. In early 1917 the admiralty officially introduced the convoy system to help reduce the losses from u-boats. The inner harbour, known as the BEDFORD BASIN, was ideal for an anchorage to assemble the convoys, and was used in both world wars.

In December 1917, the Bedford basin was full of merchant ships. The naval escort were in the outer harbour; opposite the naval installations, One of these was HMS HIGHFLYER; a Hermes class Cruiser. In August 1914 the Highflyer had caught the German ex-liner turned Armed Merchant Raider; Kaiser Wilhelm Der Grosse, refuelling at sea, and sunk her off the West African coast at Rio del oro,

The harbour was also open to neutral ships, (though their crews were not allowed ashore for security reasons). One of these was a Norwegian ship the SS IMO, she was steaming alone, and had 'Belgium Relief' written on her sides to emphasis her 'neutrality' to u-boats, she was on her way to New York to load relief supplies for Belgium. The IMO was behind schedule by having to wait for coal, with this and being empty, she may have been traveling at a faster speed than normal, when she left the Bedford Basin.

The French Ship SS MONT BLANC came from New York where she was loaded with a cocktail of explosives and volatile material. The ship had her holds lined with wood, using non sparking copper nails, but too many volatile cargoes had been mixed together. The Mont Blanc entered Halifax with 2,300 tons of wet and dry picric acid; (used for making lyddite foir artillery shells), 200 tons of trinitrotoluene, (TNT), 10 tons of gun cotton, with drums of Bezol; (High Octane fuel) stacked on her decks. The Mont Blanc was on her way to the Bedford Basin, but arrived too late to be let through the anti submarine nets, and had to wait until the next day to enter the harbour.

On the morning of the 6th December 1917, the IMO weighed anchor and headed for the sea, while the Mont BLanc entered the harbour; the collided in the bottleneck known as 'the Narrows'. Some of the Benzol drums broke loose, spilling on the deck, and soon caught fire. The intensity of the fire, and it's volatile cargo, Captain Le Medec ordered all hands to abandon ship. The Mont Blanc on fire, drifted towards Halifax where she rested against pier 6

At around 9.05 am the Mont Blanc blew up, the whole ship disintegrated. The pressure blast flattened the immediate area for two square kilometers, and devastated an area of 325 acres, most of the windows in Halifax were blown out, About 1,600 people were killed by the blast., eight crew of HMS Highflyer were splattered against the ship's superstructure, . A mushroom-shaped cloud rose kilometres high, and 3,000 tons of the splattered ship rained down on the area. The ship's gun landed near Alboro Lake (2km away), and the stock of one of her anchor's landed in a wood 5km away. The Narrows were boiling with the slashes of shrapnel, also falling were rocks;believed to had been sucked up from the harbour bed.

Next came the pressure wave which washed up the shore line and rocked the ships nearby, some from their moorings, some smaller vessels (e.g. Tugs) were overwhelmed and sunk. This man-made 'tsunami' traveled across to the shores of Dartmouth, it was funneled up Tufts cove, (due north of the explosion) where there was a settlement of the Micmac; (native American tribe of the area). The whole encampment was washed away by the gigantic wave.

The Halifax area opposite the Narrows was heavily populated, a rising hill gave an excellent view of the ship on fire. Naturally there were many spectators, which resulted in high cases of blindness/eye injuries among the thousands of wounded, as glass windows shattered.

After the blast, the rain of shrapnel, and the destructive wave, came the fires. The blast had turned houses into kindle wood, and also overturned coal and wooden stoves, which were in widespread use due to the winter temperature. Being a Naval port and Garrison town, there were lots of 'disciplined and organized' rescue workers available, but an hour after the explosion a rumour spread that the Naval Magazine at Wellington Barracks, (near Admiralty House), was on fire and there was going to be another explosion. There was a massed exodus away from the north, to citadel hill and the parks to the south. The naval magazine did not blow, and was made safe by dumping its contents into the harbour. Slowly the rescuers moved back to the area, however, by nightfall another factor was to contribute to the final death toll; the worst blizzard for years. "It was almost as if Fate, unconvinced that the exploding chemicals in the hold of the Mont Blanc had struck a death blow to Halifax, was now calling upon nature to administer the coup de grace". Other rumours were widespread. Halifax was being bombed by Zeppelins, or maybe a German Naval bombardment. Anti-German hysteria was high, which was taken out on survivors with German sounding names. Earlier in the year, in Britain, a munitions factory had blown up, even though it had been proved to be an accident, people preferred to believe it was the 'dastardly Hun'. This was proof enough, The same stubborn belief, that it was 'somehow' the work of the Germans, still persists in Halifax today, by some survivors of the explosion.
My mother's parents both lived through it (obviously ;) ). Both were only 5 at the time. The following day, the worst blizzard that had ever occurred to that date hit Halifax.
The people of Boston Massachusetts reached out with their support, and helped immeasurably in that time of great need. The city of Halifax has never forgotten that, and to this day donates a large blue spruce to the city of Boston every Christmas as a small token of thanks. We consider Boston our "sister city".
The bells still ring at the Fort Needham memorial every Dec. 6th.

Great post, trackie. :cool:
CBC also ran that two part mini-series about it last year. In it, they kind of went with that whole German sabotage angle. I was never very convinced of that myself.
Still, I thought it was a pretty good production.
I first heard about this appalling disaster in the 60's when the BBC ran a radio documentary about it A great deal of credit for helping the injured went to the local boy scout troops also in one account a witness spoke of seeing a young girl with her eye ball hanging on her cheek this was removed without the aid of anesthetics
I have never understood why it is not more widely known about I can only assume it is because it got over shadowed by events in Europe but personnely I think it,s discusting that Europe knows so little about it, as it was caused as a direct result of our allies assisting us.
trackend said:
I have never understood why it is not more widely known about I can only assume it is because it got over shadowed by events in Europe
You've probably hit the nail on the head there. Europe has had their own share of things to worry about in the twentieth century.
It'll always be remembered in Canada. Certainly by the maritime provinces in the east.
World War I over-shadowed a lot of things the influenza pandemic that killed 40 million people during 1918-1919.
The History Channel in their 'Disaster' series did a show on the Halifax explosion.
I saw that too, they were saying it was the largest man-made explosian after Hiro-saki.

Oh yeah PD I learned a bit on that, I could be thinking of another incident but did the pandemic originate from Spain. (Spanish Influenza?)

And to make things worse in the present, SARs is in the past, and a newer more deadly flu virus is loose in Toronto, its already accounted for something like 16 people dead.
In Texas on Arpil 16 1947, another massive explosion, that fortunatley didnt kill as many people.

"TEXAS CITY DISASTER. One of the worst disasters in Texas history occurred on April 16, 1947, when the ship SS Grandcamp exploded at 9:12 A.M. at the docks in Texas City. The French-owned vessel, carrying explosive ammonium nitrate produced during wartime for explosives and later recycled as fertilizer, caught fire early in the morning, and while attempts were being made to extinguish the fire, the ship exploded."

"The entire dock area was destroyed, along with the nearby Monsanto Chemical Company, other smaller companies, grain warehouses, and numerous oil and chemical storage tanks. Smaller explosions and fires were ignited by flying debris, not only along the industrial area, but throughout the city. Fragments of iron, parts of the ship's cargo, and dock equipment were hurled into businesses, houses, and public buildings. A fifteen-foot tidal wave caused by the force swept the dock area. The concussion of the explosion, felt as far away as Port Arthur, damaged or destroyed at least 1,000 residences and buildings throughout Texas City"

"Probably the exact number of people killed will never be known, although the ship's anchor monument records 576 persons known dead, 398 of whom were identified, and 178 listed as missing. All records of personnel and payrolls of the Monsanto Company were destroyed, and many of the dock workers were itinerants and thus difficult to identify. Almost all persons in the dock area-firemen, ships' crews, and spectators-were killed, and most of the bodies were never recovered; sixty-three bodies were buried unidentified. The number of injured ranged in the thousands"
The one youre thinking of was the "port Chicago" incident in 1944.
"On the night of 17 July 1944, two transport vessels loading ammunition at the Port Chicago, California naval base were suddenly engulfed in a massive explosion. The blast destroyed everything within a one-mile radius, including the two ships, the pier and the dock. It killed 320 men on the base, and injured nearly 400 more, most of whom were black. Also almost completely destroying the town of Port Chicago 1.5 miles away, it was the worst home-front military disaster of World War II."
I know this is and Old thread but I found these pictures recently of the Halifax Explosion taken from 13 miles away and a panorama of the devastation and thought it would be worth adding them.


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