The Halifax Explosion occurred on Thursday December 6 1917 at 9:04:35 a.m. local time in Halifax, Nova Scotia in Canada, when the French munitions ship Mont-Blanc, bound for World War I France, collided with the Norwegian ship Imo chartered to carry Belgian relief supplies. In the aftermath of the collision, Mont-Blanc caught fire and exploded, killing 2,000 people and injuring thousands more. The explosion caused a tsunami, and a pressure wave of air that snapped trees, bent iron rails, demolished buildings, and carried fragments for kilometres. This was the largest artificial explosion until the first atomic bomb test explosion in 1945 and still ranks highly among the largest artificial non-nuclear explosions.

Events

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On December 1 1917 Mont-Blanc a 3121-ton freighter, nearly 100 m long, departed New York City as part of a convoy bound for Halifax. On board it carried:

223 tonnes		benzol
56 tonnes		nitrocellulose
1602 tonnes		wet picric acid
544 tonnes		dry picric acid (highly explosive, and extremely sensitive to shock)
227 tonnes		TNT

On December 5, Mont-Blanc, captained by Aimé Le Médec, arrived at the examination point at McNabs Island and was waiting to be let into the harbour, but was too late. Halifax harbour had two antisubmarine nets that were closed for the night at sundown. These nets prevented both submarines and surface ships from entering or exiting. These nets were in place because of the World War and the fear of the Germans invading the Harbour. At the same time Imo, captained by Hakron From, was to sail for New York, but its coal supplier arrived late and they, too, missed the sunset cutoff time.

The next morning, December 6, Imo attempted to depart through the right channel but another ship was blocking its way. As a result, Imo started out through the left channel. Mont-Blanc was entering via the left channel at the same time, and both refused to yield. Eventually, Le Médec ordered Mont-Blanc to pass Imo and go into the center channel. Imo then stopped, but the backward action of the propellers brought her to the center channel where the two ships collided. Imo attempted to pull back, which generated sparks that quickly ignited vapours from Mont-Blanc’s benzol cargo, which was stowed on deck. As the fire spread, the crew were unable to reach fire-fighting equipment and quickly abandoned ship upon the captain's orders. Fleeing in two rowboats, the crew reached safety on the Dartmouth shore as the burning ship continued to drift toward the Halifax shore. Other ships came to aid the burning Mont-Blanc, and onlookers gathered on the shore. Eventually Mont-Blanc hit the pier which allowed the fire to spread onto land. Then, at 9:04:35, the cargo of Mont-Blanc exploded. The ship was instantly vaporised in the giant fireball that rose over 1.6 km (1 mi) into the air, forming a large mushroom cloud. The force of the blast triggered a tsunami that reached up to 18 meters above the high-water mark. Imo was lifted up onto shore by this tsunami.

Over 2.5 km² of Halifax was levelled and windows were shattered as far as Truro, Nova Scotia, 100 km away. An anchor from the Mont-Blanc was found 2 km from the harbour. The disaster resulted in approximately 2,000 deaths (as many as 1,000 died instantly), 9,000 injured (6,000 seriously) and — according to one conservative estimate — roughly US$30 million (in 1917 dollars) in damage. Some 1.3 km² (325 acres) of urban/town area were destroyed, leaving 1,500 people homeless. A detailed estimate showed that of those killed, 600 were under the age of 15, 166 were labourers, 134 were soldiers and sailors, 125 were craftsmen, and 39 were workers for the railway. Many of the wounds were also permanently debilitating, with many people partially blinded by flying glass. The large number of eye injuries led to great efforts on the parts of physicians, and a collaborative effort managed to greatly improve the treatment of damaged eyes.

The deathtoll could have been worse if not for the self sacrifice of the railroad telegraph dispatch, Vince Coleman. Despite being aware of the impending explosion, he remained at his post to send out urgent messages to two incoming trains of the danger. Although Coleman was killed in the disaster, the trains heeded the warning and stopped a safe distance from the blast. Furthermore, they also relayed the message further on to alert the authorities of the crisis to enable them to respond immediately.

The novel Barometer Rising (1941) by the Canadian writer Hugh MacLennan is set in Halifax at the time of the explosion and includes a carefully researched description of its impact on the city.

Current Time

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Every Christmas, the city of Halifax donates a large Christmas tree to the City of Boston in thanks and remembrance for the help Boston provided in the time of major need.

References

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The Halifax Explosion in popular media

• The Irish Chain by Barbara Haworth Attard, ISBN 0006392156. (Fictitious novel)

External links

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• The Maritime Museum of the Atlantic on Halifax Explosion - the Halifax Book of Rembrance lists 1,951 names
• Map of Halifax as it existed in 1915 - "The Atlas of Canada" archives
• Photographs of the memorial to the Unidentified Dead, Halifax Explosion

1917 disasters | Disasters in Canada | Explosions | Fires | Halifax Regional Municipality | History of Nova Scotia

Halifaxský výbuch | Halifax-Explosion | Explosion de Halifax | פיצוץ הליפקס | ハリファックス大爆発 | Halifaxin räjähdysonnettomuus