"But we are still too far off to see with any certainty what they are like.
What is the _Mare_ itself?
A sea, according to the early astronomers?
a plain of solid sand, according to later authority?
or an immense forest, according to De la Rue of London, so far the Moon's most successful photographer?
This gentleman's authority, Ardan, would have given you decided support in your famous dispute with the Captain at the meeting near Tampa, for he says very decidedly that the Moon has an atmosphere, very low to be sure but very dense.

This, however, we must find out for ourselves; and in the meantime let us affirm nothing until we have good grounds for positive assertion." _Mare Nubium_, though not very clearly outlined on the maps, is easily recognized by lying directly east of the regions about the centre.

It would appear as if this vast plain were sprinkled with immense lava blocks shot forth from the great volcanoes on the right, _Ptolemaeus_, _Alphonse_, _Alpetragius_ and _Arzachel_.

But the Projectile advanced so rapidly that these mountains soon disappeared, and the travellers were not long before they could distinguish the great peaks that closed the "Sea" on its northern boundary.

Here a radiating mountain showed a summit so dazzling with the reflection of the solar rays that Ardan could not help crying out: "It looks like one of the carbon points of an electric light projected on a screen! What do you call it, Barbican ?" "_Copernicus_," replied the President.