Airplanes? Flying machines?
Trivia.
According to pandit Gurudatta Vidyarthi (MA in Physics, 1886; the first ever Arya-Samaj scientist) Vedic rishis knew composition of water--- and they could make it. In short: Mitra (oxygen) relates to two Varunas (hydrogen), as in the Mitravarunau (H2O).
" Let one who is desirous to form water by the combination of two substances take pure hydrogen gas highly heated, and, oxygen
gas possessed of the property rishadha, and let him combine them to form water."
Chapter II, Composition of Water, pp. 98-102