The Great Halifax Explosion Read online

  Low explosives like fireworks have been around for centuries, but the discovery of high explosives happened relatively recently. In 1863, a German scientist named Joseph Wilbrand discovered something called trinitrotoluene, which cleverly combined some pretty basic elements—carbon monoxide, hydrogen, nitrogen, and carbon—to create something truly destructive. It’s better known as TNT.

  In 1867, a Swedish inventor with 355 patents named Alfred Nobel found that nitroglycerin, an extremely unstable high explosive, could be handled safely if it were first absorbed in a porous material such as clay, sawdust, or cotton. Nobel called his invention “dynamite” and made a fortune off it.

  When Nobel’s brother Ludvig died in 1888, a French paper mistakenly thought Alfred had died, and titled his obituary “The Merchant of Death Is Dead.” When Alfred read his own obituary, he was crushed to see how he would be remembered. To change his legacy, he rewrote his will to devote 94 percent of his fortune, or about $210 million in today’s dollars, to fund five Nobel prizes to be awarded to those who had given “the greatest benefit [to] mankind” in the fields of physics, chemistry, literature, peace, and physiology and medicine, with a prize for economics added in 1968.

  It is now debatable which of Nobel’s two most famous creations has had the greatest impact on the world he left behind, but we know the production of high explosives did not end with dynamite. Four years later, in 1871, another German scientist, Hermann Sprengel, discovered a close cousin of TNT called trinitrophenol, sometimes called TNP or picric acid, which consists of carbon monoxide, carbon dioxide, hydrogen, nitrogen, and carbon. Again, it doesn’t look too scary, but the damage picric acid can do is astonishing.

  Alan Ruffman, editor and author of Ground Zero, explains that in both explosives, “the Nitro group (NO2) acts as the oxidizer, and carbon and hydrogen provide the fuel. In the explosion process, the complex molecules decompose into a simple solid (carbon) and gases (carbon monoxide, carbon dioxide, hydrogen, and nitrogen). The energy released in the breaking of the chemical bonds that bind these molecules results in the high temperature of the explosion; the high pressures are produced by the rapid expansion of the gases as they are released from the dense solid bonding.”

  Because both TNT and picric acid are designed to be incredibly destructive, they were quickly adopted for military use, with the Boer War and the Great War serving as laboratories. By 1917, picric acid had emerged as the favorite because it was shown to be 10 percent more efficient than TNT. Both can become even more destructive if you heat the contents by igniting a low explosive nearby, which will multiply the power of the TNT or picric acid.

  “She had a devil’s brew aboard,” Raddall states of the Mont-Blanc, a perfect combination of catalysts, fuel, and firepower. The ship’s manifest included 62 tons of gun cotton, 250 tons of TNT, and 2,366 tons of picric acid, the least understood of the chemicals on board, but the most dangerous.

  Picric acid is notoriously unstable, and even more so when dry, because it’s especially sensitive to friction and shock—so sensitive, in fact, that when picric acid is stored in labs, merely turning the lid of a jar of the chemical, if dried particles are stuck between the bottle and the stopper, can blow up the entire lab.

  Put it all together, and the power of Mont-Blanc’s cargo works out to about 3 kilotons of TNT—or about a fifth of the 15 kilotons the “Little Boy” atomic bomb unleashed on Hiroshima.

  After the shipwrights had so carefully built the magazines, hermetically sealing each compartment, and the stevedores had packed it all systematically, the French government agent operating out of Gravesend Bay received a last-minute order from his superiors in France to pack what little space remained on Mont Blanc with urgently needed benzol, an unusually volatile fuel, the latest “super gasoline.” The stevedores followed orders, swinging 494 barrels containing 246 tons of the highly combustible accelerant into a few unused spaces belowdecks, on the foredeck, and at the stern, where they stacked the fuel three and four barrels high and lashed it with canvas straps, a somewhat slapdash approach compared to the thoroughness with which the shipwrights had built the magazines. When the crew walked past the drums on deck, they could smell the unmistakable reek of the benzol.

  With the final addition of the benzol, Mont Blanc now carried an impressive array of the most dangerous chemicals known to man at that time. While benzol can’t match the pure power of gun cotton, TNT, or picric acid—all high explosives—what the stevedores probably didn’t know when they stacked the barrels of benzol on deck was that the airplane fuel needed only a spark to ignite, while picric acid doesn’t explode until it reaches 572 degrees Fahrenheit, and TNT does not detonate until it reaches 1,000 degrees. But by making the last-minute decision to store most of the fuel on the deck and the TNT and picric acid below, the crew had unwittingly constructed the perfect bomb, with the easy-to-light fuse on top, and the most explosive materials trapped in the hold below.

  Thanks to reforms instituted after Titanic sank without enough lifeboats for everyone on board, Mont-Blanc had two lifeboats with enough seats to carry all forty-one men to safety, including Captain Le Médec and Pilot Mackey, but it lacked a fire extinguisher. Instead, the ship was equipped with a connection for a pressure hose on the forward deck, which would draw its water from the sea, and two anchors that could be dropped from the bow to secure her in an emergency. As a last resort, Mont-Blanc could be scuttled by opening the seacock to flood the holds, but thanks to the ship’s history of poor maintenance, that would require a minimum of thirty minutes to coerce the rusted rivets and bolts to release the old-model valve, and another two hours for the holds to fill up with enough water to sink the ship.

  But it’s unlikely anyone gave all of this much thought, and perhaps even less likely that Captain Le Médec did, since he was still getting to know the vessel on his first round trip. Besides, a sudden shift or a single spark could render all those questions moot in a second.

  As Mont-Blanc approached her December 1 departure date, Captain Le Médec returned to the British Admiralty with his interpreter for a second meeting with Commander Coates. When Coates asked him if the fully loaded Mont-Blanc could maintain 8 knots (about 10 mph) across the North Atlantic, Le Médec consulted the ship’s incomplete logs and considered his only transatlantic trip on Mont-Blanc. He didn’t have enough data to answer Coates’s question confidently, but he admitted he did not think Mont-Blanc could keep up that pace.

  Taking all this information in, Commander Coates said, “I will have to see about that,” and left Le Médec at the table while he consulted with a superior officer. A few minutes later, Coates returned to tell Le Médec he would proceed unescorted to Halifax—the first time that port had been mentioned as a possibility—and once there, if Mont-Blanc couldn’t keep up with a convoy to Europe, Le Médec was to open the envelope Coates handed to him to reveal their secret route to Bordeaux.

  Once again, Commander Coates wasn’t casting for Captain Le Médec’s feelings on the matter, nor was he offering alternatives. Captain Le Médec was again disappointed by the plans, but he didn’t waste time trying to think of a way out of this assignment but instead how they could get across the Atlantic without blowing up.

  And so the sequence of events that brought a poorly maintained French freighter built in the nineteenth century, captained by a man unfamiliar with the ship and her cargo, into the service of the British Navy in Gravesend Bay during the most horrific war in human history was now complete: all these elements had combined in surprising fashion, with any number of safeguards eliminated, to produce a weapon of mass destruction floating up the East Coast in hopes of reaching Halifax safely. It was a fool’s mission—but then, that was the Great War’s specialty. An hour before midnight on December 1, 1917, Mont-Blanc eased out of Gravesend Bay as quietly as possible.

  The Halifax Herald reported that in the last week of November 1917 alone, the British had lost one small ship, four fishing boats, and sixteen merchantmen of 1,6
00-plus tons each, for a total of twenty-one ships in seven days, or three a day. If the Germans caught sight of Mont-Blanc and added it to the list of hits, the resulting explosion would make international news. The U-boat crew would be received in Hamburg much as Highflyer’s crew was being celebrated in Halifax—provided, that is, they lived to tell the tale.

  The Mont-Blanc’s crew scanned the surface for any signs of U-boats, watching the sky to judge the weather and feeling the roll of the ship more intimately than ever before. They could only hope the shipwrights’ work would hold up. The sailors mindlessly reached for their cigarettes, only to remember that they had no matches, because lighting a match might be enough to ignite the bomb beneath them.

  Captain Le Médec navigated up the East Coast as carefully as he could, trying to balance the competing demands of speed and caution. On the one hand, the longer he took to reach the safety of Halifax Harbour, the more time a U-boat had to find them. If Mont-Blanc bypassed a straight course to Halifax in order to hug the shoreline, where the sea was calmer but U-boats were more likely to lurk, especially near Boston, the odds went higher still.

  But if Le Médec steered straight to Halifax, Mont-Blanc’s bow would pound into the bigger waves kicking up on the North Atlantic, with each impact threatening to disturb the cargo below. Even a sudden shift of the high explosives, separated only by plywood partitions, could send them to the sky. The French government marine services ordered Le Médec to stick to the coast and not worry about the time the route would add to his itinerary. Hugging the shoreline, he was able to push Mont-Blanc to 7 knots, or about 8 miles per hour, almost full speed.

  The decision seemed prescient on Mont-Blanc’s second day at sea, when a northwest gale blew across Maine for two days. As the ship fought the wind and waves, it was clear the threat of Mont-Blanc blowing itself up was greater than that of a U-boat finding her to do the job. Le Médec rode up the Maine coast almost to the Canadian border, cut across the Bay of Fundy to the southern end of Nova Scotia, and then stayed within 10 miles of the coast the rest of the way. This route, past Boston and Portland, added some 150 miles, but time seemed no object when Le Médec’s main concern was not being reduced to shrapnel.

  On the morning of Monday, December 3, Commander Coates’s New York office sent a standard coded telegram to officials at Halifax Harbour informing them of Mont-Blanc’s cargo and scheduled arrival early on Wednesday, December 5. F. Evan Wyatt, Halifax’s CXO, received the telegram. Though he did not know that picric acid was a high explosive used to make shells, he did know, like almost everyone else connected to this story, that benzol was “very dangerous,” and that TNT was a high explosive “by reputation.” He also knew other officers received copies of the telegram, but he never confirmed if any had read it.

  Le Médec and his crew knew the only real solution to their dilemma could be found inside Halifax Harbour. So it was with great relief that on Tuesday, December 4, a crewmen finally spotted Nova Scotia and yelled the good news across the deck. But what they had sighted was only the southern tip of the banana-shaped province, leaving some 250 miles to go to reach of Halifax Harbour, more than a full day’s sailing at Mont-Blanc’s top speed. As the Mont-Blanc crew finished dinner on board Tuesday night, they hoped it was their last one at sea before they sighted the Sambro Island Lighthouse on Chebucto Bay, which promised calm waters the rest of the way to Bedford Basin.

  That night, Haligonians were relaxing at home with newspaper stories about the bravery of the Nova Scotia Highland regiment during the Third Battle of Ypres, also known as Passchendaele, where millions of shells filled with picric acid claimed 600,000 casualties to gain a few more yards of soggy turf. But they were heartened by the courage of their boys, and felt like the war might be slowly moving in the right direction, especially with the Americans finally on board.

  The far more humble Imo left Rotterdam in mid-November 1917 carrying nothing except ballast, the crew, and Captain From’s loyal dog. On Monday, December 3, Imo cruised into Halifax Harbour, where Captain From planned to refuel before heading on to New York to load relief supplies, then return to Europe.

  Though a neutral ship, the Imo was still subject to wartime scrutiny to protect against spies, contraband, and attack, especially at a harbor as crucial to the Allied war effort as Halifax. Imo had to be cleared by authorities from both the Royal Canadian Navy and customs, and her crew was not allowed to communicate with anyone on shore. Imo’s neutral status also meant it ranked below the warships that moved troops, supplies, and munitions, which could create delays in getting everything from coal to permission to leave the harbor that could stretch to weeks.

  After anchoring Imo on the Halifax side of Bedford Basin, Captain From ordered fifty tons of coal from Pickford and Black, based right in Bedford Basin. After waiting two days, Captain From expected Pickford and Black to deliver the coal on Wednesday, so he asked CXO Wyatt to send a harbor pilot that day to lead his ship out to sea that afternoon. Wyatt obliged by assigning William Hayes, one of the best.

  When dawn broke on Wednesday, December 5, 1917, Imo’s mission seemed as simple as Mont-Blanc’s was nerve-racking.

  Chapter 13

  December 5, 1917

  At about 2:30 on Wednesday, December 5, Halifax customs officer Arthur G. Lovett received the Imo’s clearance papers from Naval Control, reported that fact to the guard ship, HMCS Acadian, and then boarded Imo to give Captain From the good news that his ship was cleared to go.

  But when Lovett reached From’s cabin, he found the captain agitated. The coal tender from Pickford and Black was supposed to arrive two hours earlier, but was just pulling alongside Imo with its load when Lovett arrived. Captain From knew loading the coal would take at least a couple of hours, and they would not be able to get past the submarine gates before Wyatt ordered them shut for the night.

  After Lovett disembarked from Imo, he failed to inform the guard ship that Imo would not be leaving that day but the following morning. Lovett explained later, “We never stopped at the guard ship on the way back. Our only purpose is to inform them what ships were going to clear,” not which ones would be staying in the harbor to clear later.

  When he learned Imo wouldn’t leave until the next morning, Harbour Pilot William Hayes hopped onto a tugboat heading back to the wharf so he could enjoy a few precious hours to himself, and get a good night’s sleep. But unlike Lovett, Hayes stopped by the pilotage office to inform fifteen-year-old Edward Beazley that Imo would remain at anchor in the basin for one more night, then go out first thing the next morning. Hayes then told shipping agent George R. Smith that he would get back on Imo at 7:30 a.m. to pilot the ship out of the harbor.

  Beazley dutifully wrote down the information on the blackboard, but he did not pass it on to the CXO’s office on Niobe. The following morning, Thursday, December 6, Beazley assumed that whoever needed to see the message he’d left had already seen it, so he erased it. CXO Evan Wyatt remained unaware of Imo’s status, as did the rest of the harbor officials.

  While Captain From stewed about being trapped inside Bedford Basin, Captain Le Médec and his crew were just as anxious to get in.

  In the early afternoon of Wednesday, December 5, 1917, Mont-Blanc’s fourth full day out of Brooklyn, Le Médec and his crew spotted the Sambro Island Lighthouse. They still had 18 miles to go to reach Bedford Basin, where they hoped to spend their first quiet night in four days, but just reaching the calmer waters past the lighthouse offered some peace. Their first fear, of a big wave jostling their cargo and setting off the explosives, was behind them. All they had to do now was steer their ship past the ten minesweepers keeping the entrance clear and head to Bedford Basin. Once anchored, their second fear—of getting hit by a U-boat torpedo or mine—could also be put to bed for a few days of rest and relaxation.

  Around 4:00 p.m. that day, Le Médec stopped Mont-Blanc at the examination anchorage near McNab’s Island so harbor pilot Francis Mackey could board. What time CXO Wyatt ordered t
he antisubmarine gates closed each night depended on what ships were scheduled to leave and when. But if no special arrangements had been made, he usually closed them by sundown. When the gates slammed shut, they sent a visible vibration through the buoys holding them up.

  On Wednesday, December 5, 1917, sundown would not officially occur until 5:06 p.m. Atlantic Time, but there were no ships scheduled to enter or exit, the sun had already slid behind the slope of Richmond, and darkness was descending fast. Wyatt ordered the gates closed at 4:30.

  Since the war had started, all ships were inspected before entering the harbor to prevent a Trojan horse from sneaking in and wreaking havoc. At 4:36 p.m., six minutes after Wyatt had closed the gates, Terrance Freeman, one of Wyatt’s examining officers, boarded Mont-Blanc, interviewed Le Médec in the captain’s cabin, and inspected the cargo list, a routine part of Freeman’s job.

  But when he scanned Mont-Blanc’s manifest, he could see there was nothing ordinary about the cargo sitting beneath him. Halifax Harbour welcomed thousands of ships every year, but it was still rare during the Great War for ships carrying high explosives to enter port. In fact, Freeman thought Mont-Blanc might be the first one cleared to anchor in Bedford Basin. “I knew it could do some damage all right,” he said.

  But the examination office had no special procedure for handling particularly dangerous ships. Freeman’s task was simply to ensure that the manifest accurately reflected the cargo aboard, which it did. When Freeman handed the manifest back to Le Médec, he said, “She can’t go in until morning.”

  Any chance Le Médec might have had to appeal the decision and ask for special clearance ended when CXO Wyatt left the Examiners’ Office on Niobe at 5:15 for a business meeting, after which he planned to attend a party with his wife to celebrate a friend’s wedding. The Mont-Blanc’s crew anchored just outside the harbor.