Of the origin of Bookselling, considered as a regular branch of trade, nothing certain is known. Though written or copied works circulated to some extent among the more privileged and wealthy of the ancient Greeks and Romans, there is no reason to believe that any particular person or persons, made it their trade or profession to sell those books in Greece or Rome. The first mention of Bookselling as a regular trade, occurs in some of the French historians, who state that at the twelfth century there existed at Paris and Bologna, a class of persons who dealt in books. The purchasers were almost exclusively, if not altogether so, members of the universities of these two places. The Booksellers of that period did not keep shops: it is not probable that their sales were sufficiently extensive to afford such an amount of profit as would have enabled them to pay the rent of a shop. They kept their books on portable stalls in the streets, similar to those which are still to be seen in London. It would appear, if Hallam, in his “History of the Literature of Europe,” be correctly informed, that the practice of publishing books on commission then prevailed.