Mallets Mortar, Fort Nelson near Portsmouth, Hampshire
N 50° 51.600 W 001° 08.291
30U E 631031 N 5635908
This hugh mortar and some of its shells stand outside The Royal Armouries Museum at Fort Nelson situated on Portsdown Hill north of Portsmouth.
Waymark Code: WM5RHR
Location: United Kingdom
Date Posted: 02/07/2009
Views: 12
This massive mortar was proposed by Robert Mallet, a civil engineer, and was designed to bombard Sebastapol during the Crimean War.
The Crimean War of 1854 called for a mortar that could be easily transported but was of sufficient size, and therefore calibre, to lob a heavy projectile over the walls of the fortress of Sebastopol. The weapon was made in pieces so it could be transported to Crimea and erected within a few hundred of the walls of the city.
The mortar was to sit on a platform comprised of three layers of heavy baulks of timber, this resting on a sloping bank of earth at an angle of 45 degrees. This meant that no bed was needed. The relatively small distance to the target meant that a light charge and a small chamber would suffice. Mallet's mortars were soon to be recognised as unsurpassable pieces of ordnance in respect of the weight of metal they were intended to throw and when constructed one did actually throw a shell of 2,400 lbs a distance of 1½ miles. The heaviest shell fired weighed 2,986 lbs. Until this date mortars such as the long-range 13-inch ones employed by the French at the Siege of Calais in 1810, and the Liège 24-inch mortars of 7-tons used at the siege of the Antwerp Citadel in 1832 were the largest ordnance around.
Information from the Palmerston Forts Society- (
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