"We are friends," replied Carthoris. "This be the princess, Thuvia of Ptarth, who was captured by the Torquasian horde. I am Carthoris of Helium, Prince of the house of Tardos Mors, Jeddak of Helium, and son of John Carter, Warlord of Mars, and of his wife, Dejah Thoris."
"'Ptarth'?" repeated the man. "'Helium'?" He shook his head. "I never have heard of these places, nor did I know that there dwelt upon Barsoom a race of thy strange color. Where may these cities lie? From our loftiest tower we have never seen another city than Lothar."
Carthoris pointed toward the northeast.
"In that direction lie Helium and Ptarth," he said. "Helium is over eight thousand haads from Lothar, while Ptarth lies nine thousand five hundred haads northeast of Helium."[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.
