## Bīrūnī, Muḥammad ibn Aḥmad, Alberuni's India (v. 2)

(London :  Kegan Paul, Trench, Trübner & Co.,  1910.)

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 ``` 70 ALBERUNTS INDIA. whilst Varahamihira reckoned the sun's distance from the earth as 2,598,900, and the distance of the fixed stars as 321,362,683. Thereupon Pulisa replied that the for¬ mer numbers were minutes, the latter yojctnas; whilst in another passage he says that the distance of the fixed stars from the earth is sixty times larger than the distance of the sun. Accordingly he ought to have reckoned the distance of the fixed stars as 155,934,000. "Hindu The Hindu method of the computation of the dis- thecompu- tauccs of the planets which we have above mentioned tationofthe .-i -, ..,,.,. , , •,! distances of IS Dased ou a principle which is unknown to me m the the planets. , , p i -. -. -. , t i present stage of my knowledge, and as long as i have no facility in translating the books of the Hindus. The principle is this, that the extension of a minute in the orbit of the moon is equal to fifteen yojctncts. The nature of this principle is not cleared up by the commentaries Quotations of Balabhadra, whatsoever trouble he takes. For he from Bala- -n i i • t n t i bhadra. says: " Peoplc have tried to fix by observation the time of the moon's passing through the horizon, i.e. the time between the shining of the first part of her body and the rising of the whole, or the time between the beginning of her setting and the completion of the act of setting. People have found this process to last thirty-two minutes of the circumference of the sphere." However, if it is difficult to fix by obser¬ vation the degrees, it is much more so to fix the minutes. Further, the Hindus have tried to determine by observation the yojctncts of the diameter of the moon, and have found them to be 480. If you divide them by the minutes of her body, the quotient is 15 yojctnas, as corresponding to one minute. If you multiply it by the minutes of the circumference, you get the product 324,000. This is the measure of the sphere of the moon which she traverses in each rotation. If you multiply this number by the cycles of the moon in a kalpa or caturyugct, the product is the distance which ```