Hindu Achievements in Exact Science: A Study in the History of Scientific Development c15.11

c15.11

4. Time and Space: In order to be precise and definite in their calculations the Hindus conceived infinitesimally small magnitudes of time and space. The instruments of measurement were crude. The attempt to distinguish from one another the varying grades of "least perceptible" sound, light, heat, time, etc., has therefore to be taken for what it is worth. An atom (*truti*) of time was regarded as equal to 1/33750th of a second. The thickness of the minimum visible (*trasa-renu*), e.g., the just perceptible mote in the sunbeam, was known to be 1/349525th of an inch. The size of an atom was conceived to be less than π.3.5⁻¹.2⁻⁶² of a cubic inch. "Curiously enough, this is fairly comparable (in order of magnitude) with the three latest determinations of the size of the hydrogen atom."⁵⁹ No unit of velocity seems to have been fixed upon. But average velocity was measured in accordance with the formula v = s/t. These measurements were not arbitrary poetic guess-works. It is on the basis of these that a remarkably accurate measurement of the relative pitch of musical tones was made, and the instantaneous motion of a planet determined (and thus the "principle" of the differential calculus discovered).