It is a larger achievement, one of the greatest,[24] to heighten epic by suggesting vast reaches of time, from tribal wanderings through wars of conquest to the reign of law. Here is the artistic significance of the visit in Book VI to the world of the dead and the unborn, which, as Mackail says, “slips in the keystone.” To compare the visit of Odysseus to the shades is to see Vergil’s higher art of composition. But the suggestion of the great loom of time (_tot volvere casus_) is not confined to a single artistic device; it is pervasive from the opening words through a hundred careful allusions; and it makes the _Æneid_ wider than the _Iliad_ or the _Odyssey_ by making it constantly suggestive of the whole struggle of history. It reveals more explicitly the struggles of heroic men as the struggle of man. Thus the oft-repeated objection that the _Æneid_ breaks into halves is superficial. The break would not have been thought of if Vergil had not been seen to be working for a continuity stricter than Homer’s. Stated baldly by Tyrrell, the idea that the _Æneid_ is an _Odyssey_ plus an _Iliad_ presupposes a sort of imitation to which Vergil shows himself everywhere superior. It would be as near the truth to reply that the _Æneid_ is neither an _Odyssey_ nor an _Iliad_. But prototypes aside, how and how far is the _Æneid_ held together? Surely by the most careful articulation ever seen in epic, but surely not to the degree of drama. Among the evidences of revision are indications that the plan for the wanderings of Æneas was first achieved[25] when much of the poem was already written. The adjustment of this part to the whole course, a technic hardly explored by Homer, and the abbreviations of the wanderings by careful selection, are of a piece with the consistent connection by repetition of the theme, from the opening lines, Trojæ qui primus ab oris Italiam, fato profugus, throughout the whole poem. True, the seventh book invokes Erato for scenes of battle. Maior rerum mihi nascitur ordo; Maius opus moveo. The following scenes are different, but not the theme. The art that deliberately avoided Homer’s succession of battles by interposing such scenes as Evander’s achieved more than variety. It suggests again and again what the battles were for. The close upon the tragic death of Turnus becomes more than the personal victory of the hero; it is the triumph, over _violentia_, over such individual prowess as Homer glorified, over personal ambition thwarting the state, of fortitude bringing in religion and law.