In spite, however, of the artificial restrictions placed on the intermarrying of the castes, the mingling of the two races seems to have proceeded at a tolerably rapid rate. Indeed, the paucity of women of the Aryan stock would probably render these mixed unions almost a necessity from the very outset; and the vaunted purity of blood which the caste rules were calculated to perpetuate can scarcely have remained of more than a relative degree even in the case of the Brahman caste. Certain it is that mixed castes are found referred to at a comparatively early period; and at the time of Buddha--some five or six centuries before the Christian era--the social organization would seem to have presented an appearance not so very unlike that of modern times. It must be confessed, however, that our information regarding the development of the caste-system is far from complete, especially in its earlier stages. Thus, we are almost entirely left to conjecture on the important point as to the original social organization of the subject race. Though doubtless divided into different tribes scattered over an extensive tract of land, the subjected aborigines were slumped together under the designation of Sudras, whose duty it was to serve the upper classes in all the various departments of manual labour, save those of a downright sordid and degrading character which it was left to _vratyas_ or outcasts to perform. How, then, was the distribution of crafts and habitual occupations of all kinds brought about? Was the process one of spontaneous growth adapting an already existing social organization to a new order of things; or was it originated and perpetuated by regulation from above? Or was it rather that the status and duties of existing offices and trades came to be determined and made hereditary by some such artificial system as that by which the Theodosian Code succeeded for a time in organizing the Roman society in the 5th century of our era? "It is well known" (says Professor Dill) "that the tendency of the later Empire was to stereotype society, by compelling men to follow the occupation of their fathers, and preventing a free circulation among different callings and grades of life. The man who brought the grain from Africa to the public stores at Ostia, the baker who made it into loaves for distribution, the butchers who brought pigs from Samnium, Lucania or Bruttium, the purveyors of wine and oil, the men who fed the furnaces of the public baths, were bound to their callings from one generation to another. It was the principle of rural serfdom applied to social functions. Every avenue of escape was closed. A man was bound to his calling not only by his father's but also by his mother's condition. Men were not permitted to marry out of their gild. If the daughter of one of the baker caste married a man not belonging to it, her husband was bound to her father's calling. Not even a dispensation obtained by