Physics and Chemistry
Ancient Indian ideas of physics were closely linked with religion and theology. The universe was classified as being composed of five elements, earth, fire, water, air and ether. There was a belief that elements other than ether were atomic. Indian atomism was certainly independent of Greek influence for an atomic theory was taught by Pakudha Katyayana, an older contemporary of the Buddha, and was therefore earlier than that of Democritus.
The atom was generally thought to be eternal, but some Buddhists conceived of it as occupying space for the minutest possible duration of rime, being replaced immediately by another one. Another ancient Indian school maintained that atoms combined into molecules to form objects. Indian atomic theories were not of course based on experiments, but on intuition and logic.
Indian metallurgists gained great proficiency in the extraction of metal from ore and in metal casting. Chemistry in ancient India was the handmaid, not of technology, but of medicine. Indian chemists did succeed in producing many important alkalies, acids and metallic salts by the simple process of calcification and distillation.