The Post-Aristotelian Period

After Aristotle, the headship of the Lyceum was taken over by his pupil and almost contemporary Theophrastus (371/370–288/287 B.C.). According to Diogenes Laertius he was called Tyrtamus in his early days but Aristotle was so impressed with his eloquence that he named him Theophrastus (the divine speaker). He was a voluminous writer and Diogenes ascribed the authority of some 227 treatises to him on all sorts of subjects. Nearly all his works are lost but one can draw some conclusions from what are available at present – fragments of treatises on De signis tempestatum (pluvarium, ventorum, tempestatis et serenitatis), De ventis, and Meteorologica.

Somewhere around the time of Theophrastus, the first ever quantitative measurements of rainfall were being taken in India. The credit for the measurements goes to a resourceful Chancellor of Exchequer, Kautilya, who decided to tax the land according to the precipitation it received which presumably would be an indirect form of taxation on agricultural products.

By Asit K. Biswas, Chapter 4 of the book: History of Hydrology, 1970, North-Holland Publishing Company, Amsterdam.

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