The surface was composed of brown rock and red sand broken up into miniature hills and valleys.

There were a few traces of bygone volcanic action, but it was evident that the internal fires of this tiny world must have burnt themselves out very quickly.
"Not much to be seen here," said Redgrave, as he came up the companion-way, "and I don't think it would be safe to go out.

The attraction is so weak here that we might find ourselves falling off with very little exertion.

Still, you may as well take a couple of photographs of the surface, and then we'll be off to Phobos." Zaidie got her apparatus to work, and when she had taken her slides down to the dark-room, Redgrave turned the R.Force on very slightly and Phobos began to sink away beneath them.

The attraction of Mars now began to make itself strongly felt, and the _Astronef_ dropped rapidly through the eight thousand miles which separate the inner and outer satellites.
As they approached Phobos they saw that half the little disc was brilliantly lighted by the same rays of the sun which were glowing on the rapidly increasing crescent of Mars beneath them.