There’s a rather pleasant bridge on the Regent’s Canal, a short distance beyond the Zoo as you go from Camden. It’s known as the Macclesfield Bridge or, unofficially, as the Blow-Up Bridge. The reason for this latter nickname is, surprisingly, because this one time it got blown up. Allow me to explain.
See, legislation in the 19th century concerning explosives seems to have been based not so much on the question, “How can we prevent accidents?” as “Has an accident happened yet?” If yes, consider legislation. If not, well, let’s not rock the boat. For example, into the mid-19th century, it was all-but-legal to manufacture fireworks in your own home. Technically it was illegal, but the law was never really enforced. An Act was passed to control explosives in 1860, but it was wholly inadequate – it only specifically covered gunpowder, not the newer and more powerful explosives that were starting to appear on the scene. And again, it was not properly enforced and therefore widely ignored. In 1864, an explosives factory at Erith went up. More than twelve workers were killed, but so complete was the explosion that the final death toll is unknown – a disembodied head was found in a garden a mile away and the explosion was heard fifty miles away. The blast actually produced a mushroom cloud. Subsequent investigation revealed that gunpowder was carried around the works in open wagons, workmen wore iron-soled shoes and used iron tools, barrels leaked and, most facepalm-worthy of all, people smoked inside the powder magazines. It wasn’t so much a case of determining a cause of the blast as determining which cause. It’s still not known, as anyone who saw what happened was part of the aforementioned mushroom cloud.
And so Parliament went back to the drawing board. A new Act was brought in in 1875, despite massive and predictable opposition from the explosives industry. Unfortunately, the Act came a little too late for the crew of the barge Tilbury.
The Tilbury was one of five barges being towed by the tug Ready along the Regent’s Canal up towards the Midlands. The barge was owned by the Grand Junction Canal Company, and was used for various general cargoes. On 2 October 1874, it had two cargoes in its hold. One was six barrels of petroleum, the other was five tons of gunpowder. That enough for you? The Ready was a steam tug and the Tilbury was the first barge in the convoy. Oh, and the crew were in the habit of lighting a fire in the cabin to keep warm.
Slightly before 5.00 AM, beneath Macclesfield Bridge, what now seems inevitable happened. The Tilbury exploded. The explosion was heard as far away as Woolwich, and buildings up to a mile away were damaged. The Tilbury and the Ready were obliterated, part of the latter’s keel being found embedded in the wall of a house 300 yards away. The second barge was sunk but, fortunately, the crew escaped with minor injuries. As you might imagine, the first two vessels’ crews were not so lucky, being killed instantly.
Among the many buildings damaged were the cages at London Zoo, with several exotic birds escaping. A detachment of soldiers from Albany Barracks soon arrived on the scene, though accounts differ as to whether this was to keep order, due to fear of a Fenian bomb attack or even to protect people from escaped wild beasts. The fire brigade also arrived, though by this stage all the damage that could be done had been done.
Major Vivian Majendie of the Royal Artillery carried out an investigation into the disaster, which came to the conclusion that a naked flame had ignited petrol vapour, triggering the explosion – it was known that the convoy had been stopped just before the bridge while the crew of the Ready investigated a blue flash seen aboard the Tilbury.
Macclesfield Bridge was demolished and sunk. The canal was drained while its rubble was recovered. However, Majendie remarked that while the damage was severe, it could have been a lot worse – fortunately, at that point, the canal passes through a cutting, which served to force the worst of the blast upwards. Given the amount the blast did do, the fact that it could have been worse doesn’t really bear thinking about. Majendie finished by observing that the incident proved the necessity of the forthcoming Act.
The canal was back in use four days later, and the bridge was, of course, rebuilt. But even now, it’s never quite managed to shake off the nickname of Blow-Up Bridge.