Clay, carbon and phosphorus were key ingredients that lent special traits to the ammo
Why did rockets made in Karnataka 200 years ago make the British go all crazy? Tipu’s rockets were an enigma for the armies fighting him. They travelled longer, had metal casing and did not burst prematurely. The British took these rockets to the UK to copy them. It took them more than a decade to come up with anything that could compare. Now, the secret to Tipu’s rockets is finally out.
The rockets discovered from an abandoned well in Shivamogga are helping uncover Indian science from 200 years ago. The casings of 100 rockets like the ones used by Hyder Ali and Tipu Sultan in their wars against the British in the late 18th Century were discovered in a farm belonging to a farmer Nagaraja Rao in Nagara of Hosanagara taluk in Shivamogga some years ago. In January this year, they were confirmed to be rocket casings.
A few months later, a 1,000 more casings were recovered from the same well. The total count now is 1,700 rocket casing. The Department of Archaeology, Museum and Heritage sent these casings for tests and have unmasked some facts.
Till earlier this year, only five specimens of the Tipu rockets were known to exist, including two in the Woolwich Royal Armoury in the UK. Many of the rockets were taken by the British after the fall of Tipu and they became the basis for the Congreve rockets they developed a few years later. Tipu’s rockets the most advanced of their time but they also baffled the British. Till then rockets were used in battles only for signalling.
Hyder Ali, Tipu’s father, is credited with first using iron casings for rockets instead of wood/bamboo. It became a weapon in the hands of Tipu. Some questions the British could not answer back then were: How was iron rolled into a casing? How was rusting prevented and what prevented the rocket from exploding before reaching its destination? History documents that Tipu spent considerable time and effort on research on the rockets.
T Venkatesh, commissioner of the department, has been handling the research on the rockets. Shejeshwara Nayak of the department had earlier this year concluded that the casings found were those of Tipu era rockets.
The tests conducted on the rocket casings were ferrite microstructure test, spectroscopy and wet chemistry. And this is what they found: The explosive (gunpowder) used in the rockets had 11 per cent carbon, 9 per cent sulphur and 80 per cent nitrate. The fuse made of cotton was of 20 micron.
The rolling of the iron into casing was made possible by mixing carbon as low as 0.2 to 0.5 per cent. The low carbon content in iron made it malleable. Such low carbon levels are not known to have been used before that. Even today, it is a rarity. The rusting of the iron was prevented by using 0.1 per cent phosphorus. Though there is some rusting, the cases have held for at least 220 years.
Another thing that baffled Tipu’s adversaries was how the iron casings held up in spite of the enormous heat. Why did they not blast immediately but only after travelling for a kilometre? Tests have found that a layer of clay was coated on the inside of the iron casing before being filled up with explosives. This prevented it from blowing up the rocket immediately.
(Source: BM)
Why did rockets made in Karnataka 200 years ago make the British go all crazy? Tipu’s rockets were an enigma for the armies fighting him. They travelled longer, had metal casing and did not burst prematurely. The British took these rockets to the UK to copy them. It took them more than a decade to come up with anything that could compare. Now, the secret to Tipu’s rockets is finally out.
The rockets discovered from an abandoned well in Shivamogga are helping uncover Indian science from 200 years ago. The casings of 100 rockets like the ones used by Hyder Ali and Tipu Sultan in their wars against the British in the late 18th Century were discovered in a farm belonging to a farmer Nagaraja Rao in Nagara of Hosanagara taluk in Shivamogga some years ago. In January this year, they were confirmed to be rocket casings.
A few months later, a 1,000 more casings were recovered from the same well. The total count now is 1,700 rocket casing. The Department of Archaeology, Museum and Heritage sent these casings for tests and have unmasked some facts.
Till earlier this year, only five specimens of the Tipu rockets were known to exist, including two in the Woolwich Royal Armoury in the UK. Many of the rockets were taken by the British after the fall of Tipu and they became the basis for the Congreve rockets they developed a few years later. Tipu’s rockets the most advanced of their time but they also baffled the British. Till then rockets were used in battles only for signalling.
Hyder Ali, Tipu’s father, is credited with first using iron casings for rockets instead of wood/bamboo. It became a weapon in the hands of Tipu. Some questions the British could not answer back then were: How was iron rolled into a casing? How was rusting prevented and what prevented the rocket from exploding before reaching its destination? History documents that Tipu spent considerable time and effort on research on the rockets.
T Venkatesh, commissioner of the department, has been handling the research on the rockets. Shejeshwara Nayak of the department had earlier this year concluded that the casings found were those of Tipu era rockets.
The tests conducted on the rocket casings were ferrite microstructure test, spectroscopy and wet chemistry. And this is what they found: The explosive (gunpowder) used in the rockets had 11 per cent carbon, 9 per cent sulphur and 80 per cent nitrate. The fuse made of cotton was of 20 micron.
The rolling of the iron into casing was made possible by mixing carbon as low as 0.2 to 0.5 per cent. The low carbon content in iron made it malleable. Such low carbon levels are not known to have been used before that. Even today, it is a rarity. The rusting of the iron was prevented by using 0.1 per cent phosphorus. Though there is some rusting, the cases have held for at least 220 years.
Another thing that baffled Tipu’s adversaries was how the iron casings held up in spite of the enormous heat. Why did they not blast immediately but only after travelling for a kilometre? Tests have found that a layer of clay was coated on the inside of the iron casing before being filled up with explosives. This prevented it from blowing up the rocket immediately.
(Source: BM)
No comments:
Post a Comment