Others have made Cornelius Severus the author,[358] though it is practically certain that his description of the volcano must have occurred in his poem _On the Sicilian War_.[359] But the fact that Seneca makes no reference to the existence of any learned didactic poem on the subject carries a little more weight, and there are marked parallels between Seneca's 'quaestiones Naturales' and passages in the _Aetna_.[360] Further, the very badness of the poem makes us hesitate to place it in the Augustan period. That age, no doubt, produced much bad work as well as good, but a poem so obscure and inartistically prosaic as the _Aetna_ was more likely to be produced and more likely to survive in an imitative and uninspired age such as that which followed on the death of Augustus. But for the evidence of Seneca we should place the poem in the prosaic reign of Tiberius; the considerations adduced from Seneca lead us, though with the utmost hesitation, to place it somewhere between 57 and 79 A.D.[361] Of the lower limit there can be no doubt. The fires of the Phlegraean plains are extinct,[362] therefore the poem was composed before the eruption of Vesuvius in 79 A.D.[363] The question of the authorship of the _Aetna_ has necessarily been treated at greater length than the merits of the poem deserve. It is a work of small importance; its chief value is to show how low it was possible for Roman didactic poetry to sink. In the _Aetna_ it sinks lower than epic in the _Punica_ of Silius Italicus. That poem, for all its portentous dullness, shows a certain ponderous technical skill and literary facility. The author of the _Aetna_, though clearly a man of culture, is never at his ease, the verse is laboured and lacking flexibility, and there is no technical dexterity to compensate for a total absence of genius. The terror and beauty of the mountain crowned with snow and fire find no adequate expression in these monotonous lines. There remains a conglomerate of unoriginal and unsound physical speculation. ii COLUMELLA