Jahan Kosha Cannon

Jahan Kosha Cannon (also known as the Great Gun) literally means the Destroyer of the World. It is placed in the Topekhana a quarter of mile to the south east of the Katra Mosque, in the city of Murshidabad, West Bengal, India. Topekhana was the Nawab's Artillery Park and the entrance gate of the old capital of Bengal, Bihar and Orissa, the city of Jahangir Nagar. It is protected on the east by the Gobra Nala, locally known as the Katra Jheel. Here the Jahan Kosha Cannon is laid to rest. Earlier it rested on a carriage with wheels and was surrounded by the roots of a Peepal tree. Gradually this cannon was lifted four feet from the ground but the roots surrounded it so beautifully that it has no chance of falling down. Many people were astonished to see the big and heavy cannon hanging at a height of 4 feet. Later it was free from the tree's roots. The wheels have disappeared but the iron works of the carriage and the trunions are still visible. The cannon made of ashtadahatu or 8 metals, namely silver, gold, lead, copper, zinc, tin, iron and mercury.

The cannon is more than 7 tons heavy. It is 17 feet and 6 inches in long and 3 feet in width, it has a girth of 5 feet at the touch hole end. The circumference of its mouth is more than one feet. The radius of the silt for containing fire is one and a half inch. In order to fire this cannon, 17 kilograms of gunpowder was needed for a single shelling. The orifice is 6 inches. It still shows no sign of rust. This grand cannon was made by Janardan Karmakar, Karmakars were often blacksmiths but he was a gunsmith. He made it under the instructions of Daroga Shree Mohammad and under the supervision of Hara Ballav Das in 1637 AD. He was from Dacca. The cannon was named in Dacca, when Shah Jahan was the Mughal emperor at the instance Islam Khan was the Subahdar of Bengal. It has been confirmed by an inscription engraved ob it. However, the cannon has several other names like the "Great Gun", the "Destroyer of the world", the "Conqueror of the universe", the "World Sub-duer" and so on.

The cannon is maintained by the Archaeological Survey of India.