Hindu Achivements in Exact Science: A Study in the History of Scientific Development:

blades was learned by the Saracens from the Persians who had obtained it from the Hindus. They also made gunpowder and fireworks and preparations of cements. So early as the sixth century the mercurial operations alone were nineteen in number. Pliny, in the first century, "noted the industrial position of the Hindus as paramount in the world." The preparation of fast dyes and the tempering of steel were two original and important discoveries made by them. Even in medicine and surgery they h...