The Halifax explosion of 1917, largest explosion on earth before the atomic bomb was invented... and it happened in peacetime, by accident, in the middle of the downtown harbor

The Halifax Explosion occurred 20 minutes after a Norwegian ship, the Imo, and a French ship, the Mont Blanc, collided in the harbour. The Mont Blanc was carrying picric acid (a high explosive) in its forward hold, gun cotton in its centre hold and TNT aft.

On deck it had barrels of aviation gasoline. The collision broke open the barrels of gasoline, created sparks that set it on fire and sent the flaming gasoline into the forward hold. Twenty minutes later, the ship exploded with one-seventh the power of the first atomic bomb.

The explosion destroyed everything within 800 metres and damaged everything within 1,600 metres. It also started hundreds of fires. Many persons were injured when hit by flying glass (they had been watching the fire out the window.) Others were trapped in their damaged homes and burned to death when stoves tipped over.

The explosion also created a tidal wave that lifted ships out of the water dropping one smaller boat, the Hilford, among debris on the docks. Many details of what happened were kept secret because the explosion caused severe problems for the Canadian Army. Most of the wooden buildings at Wellington Barracks, east of the main impact area, were damaged, destroyed or set on fire. The Armory, where recruits were drilling, was a wreck. The girders in the roof were broken, rendering the building unsafe. Fourteen soldiers were killed, 399 injured and 39 were still missing six weeks after the explosion. Eighty per cent of these casualties were at the Wellington Barracks.

At 8:00 p.m. on the day of the explosion, Dr. William Edwards Ladd received a call from the Boston Metropolitan Chapter of the American Red Cross asking him to take charge of the Red Cross hospital unit to be sent to Halifax. If he would find 30 doctors and 50 nurses who could leave the next morning, the Red Cross would provide all supplies.

The train was delayed leaving because so much equipment had to be loaded, especially the Harvard hospital supplies that had originally been intended for the war-front in France. The supplies from Harvard were sufficient to set up a fully equipped 500–bed hospital complete with staff.

Nova Scotia still sends a thnk you christmas tree to Boston every year... nearly 100 years later

http://www.exporail.org/can_rail/Canadian%20Rail_no461_1997.pdf

the remains of pumper Patricia, the first mechanized pumper in Canada. It was later repaired and remained in operation until 1942

http://exhibits.hsl.virginia.edu/halifax/relieftrains/

the book Explosion In Halifax Harbor

http://members.kos.net/sdgagnon/cna.html