outer verge of the Land of Awful Shadow. The Thorians alone of all the races of Pellucidar ride the lidi, for nowhere else than beside the dark country are they found."
"What is the Land of Awful Shadow?" I asked.
"It is the land which lies beneath the Dead World," replied Dian; "the Dead World which hangs forever between the sun and Pellucidar above the Land of Awful Shadow. It is the Dead World which makes the great shadow upon this portion of Pellucidar."
I did not fully understand what she meant, nor am I sure that I do yet, for I have never been to that part of Pellucidar from which the Dead World is visible; but Perry says that it is the moon of Pellucidar—a tiny planet within a planet—and that it revolves around the earth's axis coincidently with the earth, and thus is always above the same spot within Pellucidar.
I remember that Perry was very much excited when I told him about this Dead World, for he seemed to think that it ex-
