History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c24.s6.12

v1.c24.s6.12

Rain gauging was prevalent in India even before Pāṇini (III. 4.32) who provides for terms referring to measures of rainfall. The Arthaśāstra (II. 5.7) describes the rain-gauge as a basin with a mouth one aratni (= 24 aṅgulas) in width. According to the Bṛhatsaṃhitā (XXIII.2) the raingauge is to be one hasta or cubit (18 inches) in diameter. When filled to the brim it indicates 50 palas or 1 āḍhaka of rainfall. Parāśara (as quoted by Bhaṭṭotpala on Bṛh. S. XXI.32) mentions a raingauge 20 aṅgulas (15 inches) in depth and 8 aṅgulas (6 inches) in diameter. When filled to capacity, it indicates one āḍhaka rainfall. Parāśara equates four āḍhakas to one droṇa. He mentions another method of measuring rainfall. Water spread over one dhanuṣ (=4 cubits) of land indicates one droṇa of rainfall. But, in the Kṛṣi-Parāśara (verse 26) the measurement of one āḍhaka of rainfall differs radically. It says that an āḍhaka measure of water is a hundred yojanas wide and thirty yojanas deep.