we know that the principal freight of the ships which traded between Alexandria and Rome and Constantinople was corn, and that other merchandize was taken on board the corn fleets only on particular occasions, or, where it was necessary, to complete the cargoes.  Among the other edicts of Justinian, regulating the trade of Egypt, there is one which seems to have been passed in consequence of the abuses that had crept into the trade of corn and other commodities, which were shipped from Alexandria for Constantinople.  These abuses arose from the management of this trade being in the hands of a very few persons:  the emperor therefore passed a law, dividing the management into different branches, each to be held by separate individuals.  From the code of Justinian we also learn, that corn was embarked from other ports of Egypt besides Alexandria, by private merchants; but these were not permitted to export it without permission of the emperor, and even then not till after the imperial fleet was fairly at sea.  The importance of the corn trade of Egypt fully justified these laws; for at this period Constantinople was annually supplied with 260,000 quarters of wheat from this country.

The resources of the Romans were principally derived from the tribute levied on the conquered countries; but in part also from duties on merchandize:  in the latter point of view, alone, they fall under our notice.  No custom duties seem to have been imposed till the time of Augustus; but in his reign, and that of his immediate successors, duties were imposed on every kind of merchandize which was imported into Rome; the rate varied from the eighth to the fortieth part of the value of the article.  The most full and minute list of articles of luxury on which custom duties were levied, is to be found in the rescript of the emperors Marcus and Commodus, relating to the goods imported into Egypt from the East.  In the preamble to this rescript it is expressly declared, that no blame shall attach to the collectors of the customs, for not informing the merchant of the amount of the custom duties while the goods are in transit; but if the merchant wishes to enter them, the officer is not to lead him into error.  The chief and most valuable articles on which, by this rescript, duties were to be levied, were cinnamon, myrrh, pepper, ginger, and aromatics; precious stones; Parthian and Babylonian leather; cottons; silks, raw and manufactured:  ebony, ivory, and eunuchs.

Till the reign of Justinian, the straits of the Bosphorus and Hellespont were open to the freedom of trade, nothing being prohibited but the exportation of arms for the service of the barbarians:  but the avarice, or the profusion of that emperor, stationed at each of the gates of Constantinople a praetor, whose duty it was to levy a duty on all goods brought into the city, while, on the other hand, heavy custom duties were exacted on all vessels and merchandize that entered the harbour.  This emperor also exacted in a most