To these fragments of Julian calendars, all drawn up between B.C. 31 and A.D. 46, there remain to be added two in MSS.: (i) that of Philocalus, A.D. 354, (ii) that of Polemius Silvius, A.D. 448; neither of which are of much value for our present purpose, though they will be occasionally referred to. Lastly, we have two farmer’s almanacs on cubes of bronze, which omit the individual days, but are of use as showing the course of agricultural operations under the later Empire[36]. All these calendars, some of which had been printed wholly or in part long ago, while a few have only been discovered of late, have been brought together for the first time in the first volume of the _Corpus Inscriptionum Latinarum_, edited by Mommsen with all his incomparable skill and learning, and furnished with ample elucidations and commentaries. And we now have the benefit of a second edition of this by the same editor, to whose labours in this as in every other department of Roman history it is almost impossible to express our debt in adequate words. All references to the calendars in the following pages will be made to this second edition. A word remains to be said about the _Fasti_ of Ovid[37], which is a poetical and often fanciful commentary on the calendar of the first half of the Julian year, i.e. January to June inclusive; each month being contained in one book. Ovid tells us himself[38] that he completed the year in twelve books; but the last six were probably never published, for they are never quoted by later writers. The first six were written but not published before the poet’s exile, and taken in hand again after the death of Augustus, but only the first book had been revised when the work was cut short by Ovid’s death.