the hatchway which had been opened by one of the seamen.
We found ourselves in a small subterranean vault, in the center of which was the pool in which lay our submarine, floating as we had first seen her with only her black back showing.
Around the edge of the pool was a level platform, and then the walls of the cave rose perpendicularly for a few feet to arch toward the center of the low roof. The walls about the ledge were pierced with a number of entrances to dimly lighted passageways.
Toward one of these our captors led us, and after a short walk halted before a steel cage which lay at the bottom of a shaft rising above us as far as one could see.
The cage proved to be one of the common types of elevator cars that I had seen in other parts of Barsoom. They are operated by means of enormous magnets which are suspended at the top of the shaft. By an electrical device the volume of magnetism generated is regulated and the speed of the car varied.
In long stretches they move at a sickening speed, especially on the upward trip, since the small force of gravity inherent to Mars results in very little opposition to the powerful force above.
Scarcely had the door of the car closed behind us than we were slowing up to stop at the landing above, so rapid was our ascent of the long shaft.
