A short distance away he discovered a swift-flowing subterranean stream, in which revolved a water wheel of rude, but serviceable, construction.
As nothing seemed wrong with it, he was obliged to look further, and finally found the cause of trouble to be a transmitting belt, the worn-out lacing of which had parted.

As portions of the belt itself had been caught in the pulleys and badly cut, it was necessary to hunt through the pile of material for a new one, and for leather suitable for lacing.

Then the new belt must be accurately measured, laced together, and adjusted to its pulleys.
Although the temperature of the cavern was many degrees above that of the outside air, it was still so low that Cabot worked slowly and with numbed fingers.

Thus more than an hour had elapsed before the dynamo was again in running order, and he was at liberty to return to the living room.

In the meantime his curiosity concerning this strange place of abode and its mysterious tenant was increased by the remarkable collection of articles stored on all sides.