Geometry, however, was not destined to take hold of the Indian mind. The cognate science of numbers speedily took its place, and the acute Asiatic intellect soon evolved Algebra out of the arithmetic which they had rendered of practical use by the adoption of the decimal system of notation. For all these many discoveries the world is indebted to this marvellous millennium. Regarding the social life of this time the Dharma Sûtras give us endless laws--which are the originals of later and codified laws--concerning almost every subject under the sun. As every Hindu student (and every Hindu had to be student for a definite number of years) had to learn these Sûtras by heart, it may safely be predicted that they faithfully reflect the general conduct of affairs. They are extraordinarily minute in particular, and from them it may be gathered that life had become much more artificial. Amongst the king's duties is that of "guarding household weights and measures from falsification." It may also be noticed that "the taxes payable by those who support themselves by personal labour differ materially from those paid by mere possessors of property." Any injury, also, to a cultivator's land or to an artisan's trade was punished with great severity, and violence in defence of them was held justifiable. A legal rate of interest was settled, and the laws of inheritance were laid down minutely, as also were those of marriage. Indeed, as Mr R. C. Dutt puts it:-- "Everything that was confused during the Epic period was brought to order--everything that was discursive was condemned; opinions were arranged and codified into bodies of laws, and the whole social system of the Hindus underwent a similar rigid treatment." Briefly, it was at once an age of keen speculation and rapid crystallisation almost unequalled in the history of any nation. Nor have we to found this estimate of it solely by inference from the literature which it has left behind it. We have other evidence on which to draw. True, the earliest foreign notice of India is that of Hekataios of Miletus, who wrote about B.C. 520, but he seems only to have been aware of its existence. The next is that of some inscriptions of the Persian king, Darius, which may be dated about B.C. 486, while Ktesias of Knidos, who collected travellers' tales about the East, wrote a little later. But Alexander's Indian campaign, which began in the year B.C. 327, brought many Western eyes to wonder at what they saw, and from this time Greece practically gives us the chronology of Hindustan. Of what these Western eyes saw we gain glimpses in the few fragments of the works of Megasthenes which have withstood the destruction of time. Living, as he did, in the fourth century B.C. as Ambassador at the court of Pâlipûtra, he gives us a picture of the times well worth reading, with a few extracts from which this chapter may well conclude.