But, on the other hand, an examination of the poem in detail leads to the conclusion that it did not receive its author's final touch. The continuity of the argument is occasionally broken in all the books except the first. In the fourth, fifth, and sixth, especially, these breaks are very frequent, and there are more frequent instances in them of repetition and careless workmanship. They extend also to a greater length than the earlier books, which would naturally be the case if they had not received the author's final revision. The poem throughout gives the impression of great fulness of matter-- Usque adeo largos haustus e fontibu' magnis Lingua meo suavis diti de pectore fundet;-- and in the composition of these later books, new suggestions seem to have been constantly occurring to the poet as new materials were added to his stores of knowledge: and the first draft of his argument has not been recast so as to incorporate and harmonise them with it. The passages containing these new materials appear to have been fitted into the place which they now occupy in the work, not always very judiciously, either by Cicero or some other editor. It was also part of the author's design to enunciate his deepest thoughts on the Gods, on Nature, and on human life in more highly finished digressions from the main argument. Such passages are, in general, introduced at the beginning and the end of the different books. They seem to bring out the more catholic interest which underlies the special subject of the poem. Some of these passages are highly finished, and were evidently fixed by the poet in the places which he designed them to occupy. Such are, especially, the introductions to the first, second, and third books, and the concluding passages of the second and third. But the repetition of a passage of the first book as the introduction to the fourth, the long break in the continuity of the introduction to the fifth, the unfinished style of that to the sixth, and the abrupt and episodical conclusion to the whole poem (when contrasted with its elaborately artistic introduction), show that the same cause which marred the symmetry of his argument deprived it of the finished execution of a work of art. Yet these books--especially the fifth--are as rich in poetical feeling and substance as the earlier ones. The eye and hand of the master are as powerful as in the first enthusiasm with which he dedicated himself to his task, but they are less certain in their action. Whether his powers became intermittent owing to the attacks of illness, or whether his habit was to work roughly in the first instance and to perfect his work by subsequent revision, which in the case of his latest labours was prevented by death, must remain uncertain. It is a noticeable result of the vastness of the tasks which Roman genius set before itself, that two such works as the didactic poem of Lucretius and the Aeneid of Virgil were left