The traffic in slaves was, next to that in corn, of the greatest consequence to the Athenians, for the citizens were not in sufficient numbers, and, if they had been, were not by any means disposed, to cultivate the land, work the mines, and carry on the various trades and manufactures.  The number of slaves in Attica, during the most flourishing period of the republic, was estimated at 400,000:  of these the greater part had been imported; the rest were natives of Greece, whom the fate of arms had thrown into the hands of a conqueror irritated by too obstinate a resistance.  The slaves most esteemed, and which brought the highest price, were imported from Syria and Thrace, the male slaves of the former country, and the females of the latter:  the slaves from Macedonia were the least valued.  The price of a slave seems to have been extremely low, as Xenophon mentions that some were sold at Athens for half an Attic mina, or rather more than thirty shillings:  those, however, who had acquired a trade, or were otherwise particularly useful, were valued at five minae, or about fifteen pounds.

Our idea of the commerce of Athens, and of Greece in general, would be very imperfect and inadequate if we neglected to notice their fairs.  It has been ingeniously supposed, that at the celebrated games of Greece, such as those of Olympia, &c., trade was no subordinate object; and this idea is certainly confirmed by various passages in ancient authors.  Cicero expressly informs us, that even so early as the age of Pythagoras, a great number of people attended the religious games for the express purpose of trading.  At Delphi, Nemaea, Delos, or the Isthmus of Corinth, a fair was held almost every year.  The amphyctionic fairs were held twice a year.  In the time of Chrysostom, these lairs were infamously distinguished for a traffic in slaves, destined for public incontinence.  The amphyctionic spring fair was held at Delphi, and at Thermopylae in the autumn; in fact, at the same times that the deputies from the states of Greece formed the amphyctionic council;—­another proof that wherever large assemblies of people took place in Greece, for religious or political purposes, advantage was taken of them to carry on traffic.  At the fairs of Thermopylae medicinal herbs and roots, especially hellebore, were sold in large quantities.  One principal reason why the religious games or political assemblies of the states were fixed upon to hold fairs was, that during them all hostilities were suspended; and every person might go with his merchandize in safety to them, even through an enemy’s country.  The priests, so far from regarding these fairs as a profanation of the religions ceremonies, encouraged them; and the priests of Jupiter, in particular, advanced large sums on interest to such merchants as had good credit, but had not sufficient money with them.