he said. "Helium is over
eight thousand haads from Lothar, while Ptarth lies nine thousand
five hundred haads north-east of Helium."[1]

[1]On Barsoom the AD is the basis of linear measurement. It is
the equivalent of an Earthly foot, measuring about 11.694 Earth
inches. As has been my custom in the past, I have generally
translated Barsoomian symbols of time, distance, etc., into their
Earthly equivalent, as being more easily understood by Earth readers.
For those of a more studious turn of mind it may be interesting
to know the Martian table of linear measurement, and so I give it
here:

10 sofads = 1 ad
200 ads = 1 haad
100 haads = 1 karad
360 karads = 1 circumference of Mars at equator.

A haad, or Barsoomian mile, contains about 2,339 Earth feet. A
karad is one degree. A sofad about 1.17 Earth inches.

Still the man shook his head.

"I know of nothing beyond the Lotharian hills," he said. "Naught
may live there beside the hideous green hordes of Torquas. They
have conquered all Barsoom except this single valley and the city
of Lothar. Here we have defied them for countless ages, though
periodically they renew their attempts to destroy us. From whence
you come I cannot guess unless you be descended from the slaves
the Torquasians captured in early times when they reduced the outer
world to their vassalage; but we had heard that they destroyed all
other races but their own."

Carthoris tried to explain that the Torquasians ruled but a
relatively tiny part of the surface of Barsoom, and even this only
because their domain held nothing to attract the red race; but the
Lotharian could not seem to conceive of anything beyond the valley
of Lothar other than a trackless waste peopled by the ferocious
green hordes of Torquas.

After considerable parleying he consented to admit them to the
city, and a moment later the wheel-like gate rolled back within
its niche, and Thuvia and Carthoris entered the city of Lothar.

All about them were evidences of fabulous wealth. The facades of
the buildings fronting upon the avenue within the wall were richly
carven, and about the windows and doors were ofttimes set foot-wide
borders of precious stones, intricate mosaics, or tablets of beaten
gold bearing bas-reliefs depicting what may have been bits of the
history of this forgotten people.

He with whom they had conversed across the wall was in the avenue
to receive them. About him were