His history comprises, in twenty books, the period from the earliest times to the beginning of the first Punic war. It does not go further, either because Polybius,--for whom he has, however, no particular liking,--begins with that period, or because the much-read history of Fabius rises here into greater importance. The first ten books are complete; the eleventh is in a very corrupt state. Extracts from the others are found in the collections of Constantinus Porphyrogenitus _De Virtutibus et Vitiis_, and _De Legationibus_; and also in a collection ἐκλογαὶ Διονυσίου τοῦ Ἁλικαρνασσέως, which is met with in several libraries, but is dreadfully mutilated. Mai has published them from a Milanese manuscript; Montfaucon had already directed attention to them. I respect and acknowledge the merits of Mai; but he has an unfortunate vanity, and thus I believe, that he has intentionally foreborn to mention, that here he has been led into the right path by Montfaucon, conduct for which he has been taken to task by Ciampi. Yet this is merely a secondary question. The collection itself mostly consists of unconnected sentences, remnants perhaps of books of Const. Porphyrogenitus, which have not come down to us. The advantage gained from this discovery is at all events very considerable. Dionysius himself had made an abridgment of his work in five books, to which Mai quite wrongly wants to have those extracts referred. As to the first ten books, there are more very old manuscripts of them extant than of any other ancient author. The Chigi manuscript is of the tenth, that of the Vatican of the eleventh century; the former is kept by Fea locked up from all visitors,--it has been imperfectly collated by Amati, but the result has never been published, nor would he sell it to me; the Vatican codex has been made use of by Hudson. The eleventh book is only to be found in copies which are quite modern. Ever since the old books were no more written on rolls, those which were voluminous had stated divisions. Thus the Pandects, the Theodosian Code, Livy also, were originally divided into decades; and in all likelihood Dionysius too. Of these, the first volume has been preserved entire. Of the second, a copy very probably long existed;--Photius was acquainted with it still;--yet only a few leaves of it have come into the hands of the first Greek copyists. The text is much more corrupt than that of the first half.