In the gloomy bottom of the crater, whose dimensions are vast enough to swallow Mont Blanc body and bones, could be distinguished a magnificent group of cones, at least half a mile in height and glittering like piles of crystal.

Towards the north several breaches could be seen in the ramparts, due probably to a caving in of immense masses accumulated on the summit of the precipitous walls.
As already observed, the surrounding plains were dotted with numberless craters mostly of small dimensions, except _Gay Lussac_ on the north, whose crater was about 12 miles in diameter.

Towards the southwest and the immediate east, the plain appeared to be very flat, no protuberance, no prominence of any kind lifting itself above the general dead level.
Towards the north, on the contrary, as far as where the peninsula jutted on _Oceanus Procellarum_, the plain looked like a sea of lava wildly lashed for a while by a furious hurricane and then, when its waves and breakers and driving ridges were at their wildest, suddenly frozen into solidity.

Over this rugged, rumpled, wrinkled surface and in all directions, ran the wonderful streaks whose radiating point appeared to be the summit of _Copernicus_.

Many of them appeared to be ten miles wide and hundreds of miles in length.
The travellers disputed for some time on the origin of these strange radii, but could hardly be said to have arrived at any conclusion more satisfactory than that already reached by some terrestrial observers.
To M'Nicholl's question: "Why can't these streaks be simply prolonged mountain crests reflecting the sun's rays more vividly by their superior altitude and comparative smoothness ?" Barbican readily replied: "These streaks _can't_ be mountain crests, because, if they were, under certain conditions of solar illumination they should project _shadows_--a thing which they have never been known to do under any circumstances whatever.