"I want you to look particularly at these larger mountain-ranges, one at the right, the other at the left side of my map--each of which as it stretches out into the sea divides into two smaller chains. Upon these ranges, and the comparatively diminutive height of the intervening mountains, in connection with the fact that there is a constant wind-current from the lower Pacific (generally speaking, from the west of longitude 74 W.), depends the habitability of this large island, the Island of Hili-li (here represented in about longitude 75 E.), and many other islands which stretch out in the same direction from this enormous active surface-crater. I say that upon such conditions depends the habitability of these islands, and so I believe; but there is another cause for their greater than tropical warmth: If you will glance here on the right of this map, in the midst of the mountain zone you will see represented a bay, which, winding among mountains, makes its way very close to the zone of hot lava--in fact, is divided from it by little more than the ring of lava-blocks, rock-salt, and animal remains, which at this point is narrowed to a width of about two miles. The temperature of the water of this bay at its inner extremity is probably about 180 F.--say 32 below the boiling-point of distilled water; and it flows in a steady current past the Island of Hili-li. This bay is undoubtedly fed from the opposite side of the great crater, and its supply flows for miles in contact with hot lava. It is probable that this extremely warm water current greatly assists the hot-air current in creating the super-tropical climate of Hili-li. "And now, as I have in part satisfied your curiosity, and as I am somewhat exhausted with my two days' and nights' experience with Peters, I know you will permit me to rest at so suitable a stopping-point. To-morrow evening I will take up the story of Dirk Peters where it joins the sudden break in Pym's journal, and will carry you along to the time when the inhabitants of Hili-li thought that the atmosphere of some other land would be more conducive to Peters' longevity and health, as well as to their own tranquillity. And I assure your Sultanship, that the story I shall relate to you to-morrow night will be more interesting than the dry physical facts which I have this evening imparted, and which it seemed best that you should know before hearing in consecutive detail the particulars of Peters' voyage." I assented to his suggestions, thanking him for the clear description which he had given of that strange region, and for the pains he had taken to draft of it so accurate a map--which map he allowed me to retain. I was about to ask a question, when the door opened, and Doctor Castleton rushed into the room. "Well, how's the old man?" he asked.