Gunpowder invented in India

Military Transition in Early Modern Asia, 1400-1750: Cavalry, Guns, Government and Ships’ by Kaushik Roy.

Chemical warfare in Ancient India by Vaman R. Kokatnur J. Chem. Educ., 1948, 25 (5), p 268

https://pubs.acs.org/doi/pdf/10.1021/ed025p268