Boat world news

Auckland’s Waitemata Harbour reverberated to the sound of a 131-year old cannon in July – the ‘disappearing gun’ mounted at Maungauika/north Head Historic Reserve in Devonport. The gun – with its 8-inch bore – was built in 1886 at Britain’s Elswick Ordinance Works and mounted on North Head in the late 1800s to reprise a possible attack from the Russian Navy. Relations between expansionist Russia and Britain were a little strained at the time.

But it was never fired in anger – in fact has only ever fired a handful of times – the last to celebrate the All Black’s Rugby World Cup win in 2011. This latest event was arranged for an upcoming NZ on Air-funded documentary – Heritage Rescue – a programme described as “peeling back the layers” of Devonport’s past.

The gun was designed to retract into the ground after firing in a bid to conceal its location, which explains its nickname – the disappearing gun. Retracted below ground between shots, it could be loaded out of sight of attacking ships. It did this using the power generated by the recoil of the gun as it fired.

Very few of these guns remain anywhere in the world. The 13-ton gun barrel fired a 95kg shell using a 50kg explosive cartridge. It had an effective range of about 2,500m.

ABOVE It’s called the disappearing gun because it was designed to retract between shots. The last time the gun was fired was in 2011, to celebrate the All Blacks’ RWC victory. Photo: Chris Weissenborn.