Apparently the locality they were approaching had been set aside as a
very exclusive residence district for the elite of the country. Possibly
it contained the homes of the royalty, assuming that there had been a
royalty. At any rate the conspicuous structure Jackson had selected was
certainly the home of the most important member of that colony.

When the three, once more in their helmets and suits, stood before the
low, broad portico which protected the entrance to that edifice, the
first thing they made out was an ornamental frieze running across the
face. In the same bold, realistic style as the other sculpture, there
was depicted a hand-to-hand battle between two groups of those half
savage, half cultured monstrosities. And in the background was shown a
glowing orb, obviously the sun.

"See that?" exclaimed the doctor. "The size of that sun, I mean! Compare
it with the way old Sol looks now!"

They took a single glance at the great ball of fire over their heads;
nine times the size it always seemed at home, it contrasted sharply with
the rather small ball shown in the carvings.

"Understand?" the doctor went on. "When that sculpture was made, Mercury
was little nearer the sun than the earth is now!"

The builder was hugely impressed. He asked, eagerly: "Then probably the
people became as highly developed as we?"

Van Emmon nodded approvingly, but the doctor opposed. "No; I think not,
Jackson. Mercury never did have as much air as the earth, and