Editing Halifax Explosion (section)

===Collision and fire===
{{External media|width=210px|float=right|audio1 = [http://www.cbc.ca/archives/entry/mont-blanc-pilot-francis-mackey-recalls-halifax-1917-explosion Mont-Blanc pilot Francis Mackey recalls Halifax 1917 explosion], 6:38, [[Canadian Broadcasting Corporation|CBC Archives]]}}
''Imo'' was granted clearance to leave [[Bedford Basin]] by signals from the guard ship [[CSS Acadia|HMCS ''Acadia'']] at approximately 7:30 on the morning of 6{{nbsp}}December,<ref>{{cite web |url= http://marinecurator.blogspot.ca/2013/12/halifax-harbour-remembers-halifax.html |author= Conlin, Dan |title= The Harbour Remembers the Halifax Explosion |publisher= Maritime Museum of the Atlantic |date= 6 December 2013|archiveurl=https://web.archive.org/web/20131211220440/http://marinecurator.blogspot.ca/2013/12/halifax-harbour-remembers-halifax.html|archivedate=11 December 2013}}</ref> with Pilot William Hayes on board. The ship entered the Narrows well above the harbour's speed limit in an attempt to make up for the delay experienced in loading her coal.<ref name=nasa/> ''Imo'' met American [[Tramp trade|tramp steamer]] SS ''Clara'' being piloted up the wrong (western) side of the harbour.{{sfn|Flemming|2004|p=23}} The pilots agreed to pass starboard-to-starboard.{{sfn|Mac Donald|2005|pp=30–31}} Soon afterwards, ''Imo'' was forced to head even further towards the Dartmouth shore after passing the [[tugboat]] ''[[Stella Maris (ship)|Stella Maris]]'', which was travelling up the harbour to Bedford Basin near mid-channel. Horatio Brannen, the captain of ''Stella Maris'', saw ''Imo'' approaching at excessive speed and ordered his ship closer to the western shore to avoid an accident.{{sfn|Flemming|2004|p=24}}{{sfn|Kitz|Payzant|2006|p=17}}{{sfn|Mac Donald|2005|p=33}}

Francis Mackey, an experienced harbour pilot, had boarded ''Mont-Blanc'' on the evening of 5 December 1917; he had asked about "special protections" such as a guard ship, given ''Mont-Blanc''{{'}}s cargo, but no protections were put in place.<ref name=nasa/> ''Mont-Blanc'' started moving at 7:30&nbsp;am on 6 December and was the second ship to enter the harbour as the anti-submarine net between [[Georges Island (Nova Scotia)|Georges Island]] and [[Pier 21]] opened for the morning.{{sfn|Kitz|1989|p=15}} ''Mont-Blanc'' headed towards Bedford Basin on the Dartmouth side of the harbour.{{sfn|Mac Donald|2005|pp=15–19, 27}}{{sfn|Flemming|2004|pp=17, 22}}{{sfn|Armstrong|2002|p=32}} Mackey kept his eye on the ferry traffic between Halifax and Dartmouth and other small boats in the area.{{sfn|Mac Donald|2005|p=32}} He first spotted ''Imo'' when she was about {{convert|0.75|mi|order=flip}} away and became concerned as her path appeared to be heading towards his ship's starboard side, as if to cut him off. Mackey gave a short blast of his ship's signal whistle to indicate that he had the right of way but was met with two short blasts from ''Imo'', indicating that the approaching vessel would not yield its position.{{sfn|Flemming|2004|p=24}}{{sfn|Kitz|1989|p=15}}<ref>{{cite web |url=http://www.halifaxexplosion.org/collision3.html |author1=Ruffman, Alan |author2=Findley, Wendy |year=2007 |title=The Collision |work=The Halifax Explosion |accessdate=13 June 2015 |archiveurl=https://web.archive.org/web/20150924024640/http://www.halifaxexplosion.org/collision3.html |archivedate=24 September 2015 |url-status=dead }}</ref> The captain ordered ''Mont-Blanc'' to halt her engines and angle slightly to starboard, closer to the Dartmouth side of the Narrows. He let out another single blast of his whistle, hoping the other vessel would likewise move to starboard but was again met with a double-blast.{{sfn|Mac Donald|2005|p=38}}

Sailors on nearby ships heard the series of signals and, realizing that a collision was imminent, gathered to watch as ''Imo'' bore down on ''Mont-Blanc''.{{sfn|Mac Donald|2005|p=39}} Both ships had cut their engines by this point, but their momentum carried them towards each other at slow speed. Unable to ground his ship for fear of a shock that would set off his explosive cargo, Mackey ordered ''Mont-Blanc'' to steer hard to port (starboard helm) and crossed the bow of ''Imo'' in a last-second bid to avoid a collision. The two ships were almost parallel to each other, when ''Imo'' suddenly sent out three signal blasts, indicating the ship was reversing its engines. The combination of the cargoless ship's height in the water and the [[Propeller walk|transverse thrust]] of her right-hand propeller caused the ship's head to swing into ''Mont-Blanc''. ''Imo''{{'}}s prow pushed into the No. 1 hold of ''Mont Blanc'', on her starboard side.<ref name=nasa/>{{sfn|Mac Donald|2005|pp=40–41}}

The collision occurred at 8:45&nbsp;am.{{sfn|Flemming|2004|p=25}} The damage to ''Mont Blanc'' was not severe, but barrels of deck cargo toppled and broke open. This flooded the deck with benzol that quickly flowed into the hold. As ''Imo''{{'}}s engines kicked in, she disengaged, which created sparks inside ''Mont-Blanc''{{'}}s hull. These ignited the vapours from the benzol. A fire started at the water line and travelled quickly up the side of the ship. Surrounded by thick black smoke, and fearing she would explode almost immediately, the captain ordered the crew to abandon ship.{{sfn|Flemming|2004|p=25}}{{sfn|Kitz|1989|p=19}} A growing number of Halifax citizens gathered on the street or stood at the windows of their homes or businesses to watch the spectacular fire.{{sfn|Kitz|1989|pp=22–23}} The frantic crew of ''Mont-Blanc'' shouted from their two lifeboats to some of the other vessels that their ship was about to explode, but they could not be heard above the noise and confusion.{{sfn|Mac Donald|2005|p=49}} As the lifeboats made their way across the harbour to the Dartmouth shore, the abandoned ship continued to drift and beached herself at Pier 6 near the foot of Richmond street.{{sfn|Flemming|2004|pp=25–26}}

Towing two [[scow]]s at the time of the collision,{{sfn|Kitz|Payzant|2006|p=17}} ''Stella Maris'' responded immediately to the fire, anchoring the barges and steaming back towards Pier 6 to spray the burning ship with their fire hose.{{sfn|Mac Donald|2005|p=46}} The tug's captain, Horatio H. Brannen, and his crew realized that the fire was too intense for their single hose and backed off from the burning ''Mont Blanc''. They were approached by a [[Whaleboat|whaler]] from [[HMS Highflyer (1898)|HMS ''Highflyer'']] and later a steam [[Pinnace (ship's boat)|pinnace]] belonging to [[HMS Niobe (1897)|HMCS ''Niobe'']]. Captain Brannen and Albert Mattison of ''Niobe'' agreed to secure a line to the French ship's stern so as to pull it away from the pier to avoid setting it on fire. The {{convert|5|in|mm|adj=on|spell=in|round=5}} [[hawser]] initially produced was deemed too small and orders for a {{convert|10|in|mm|adj=on|spell=in}} hawser came down. It was at this point that the blast occurred.{{sfn|Mac Donald|2005|pp=50–51}}