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 used all over the world. The influence which the decimal system of reckoning dependent on those figures has had not only on mathematics, but on the progress of civilisation in general, can hardly be over-estimated. During the 8th and 9th centuries the Indians became the teachers in arithmetic and algebra of the Arabs, and through them of the nations of the West. Thus, though we call the latter science by an Arabic name, it is a gift we owe to India."

We have thus far attempted to present our readers with a brief, hurried and necessarily imperfect survey of the gradual evolution and development of Hindu medicine and alchemy from the Vedic age onward. We hope we have been justified in dividing this entire range into four distinct periods, each characterised by fairly well defined features. There are of course no sharp lines of demarcation—the one imperceptibly merging into the other. These are (1) The Ayurvedic Period; (2) The Transitional period; (3) The Tantric period; (4) The Iatro-chemical period.