is immediately below the summit of the pass, and may now be seen furrowed by a roaring torrent, amidst dark ledges of rock; the corresponding chasm on the southern side of the Little St Bernard is _below_ the reach of avalanches.[28] 5. On the summit of Mont Cenis is still to be seen a "_white_ rock" called the "Roche Blanche," which answers to the [Greek: "leuchopetron,"] mentioned by Polybius, on the summit of the Alps which Hannibal crossed, whereas there is nothing like it on the Little St Bernard, at least of such magnitude as to have formed a place of night refuge to Hannibal. 6. What is perhaps most important of all, it is expressly mentioned by Polybius, that "_in one day's time_ the chasm in the mountain sides was repaired, so that there was room for the horses and beasts of burden to descend. They were immediately conducted down, _and having gained_ the plains, were sent away to pasture in places where no snow had fallen. * * * * * Hannibal then descended last, with all the army, and thus, on the _third day_, gained the plains[29]." This description of the distances tallies perfectly with the passage by Mont Cenis, for it is only half a day's journey to descend from the summit of that pass to Susa, at the head of the wide and open valley of the same name, where ample pasturage is to be found; and short day's journey more brings the traveller to the plain of Piedmont. But it is utterly irreconcilable with the idea that the Carthaginians passed by the Little St Bernard; for from its summit to the plains of Ivrea is four days' hard marching for an army, through the narrow valley of Aosta, destitute for the most part of forage. 7. This valley of Aosta is very rocky and narrow, and affords many positions where a handful of men can arrest an army; in one of which, that of Bard, a small Austrian garrison stopped Napoleon for twenty-four hours; yet Polybius and Livy concur in stating, that after he descended the mountains, the Carthaginians experienced no molestation on their way to the Insubrians, their allies, on the banks of the Po. This is inexplicable if they were struggling for three days through the narrow and rocky defiles of the valley of Aosta, but perfectly intelligible if they were traversing in half a day the broad and open valley of Susa, offering no facilities to the attacks of the mountaineers.