ble improvements which might have been made in it. He knew that it
was an apparatus for lowering the car to a great depth, and, climbing
into the car, he examined everything it contained. Coming down, he
noticed the grating, and he knew what it was for. He looked over the
engines and calculated the strength of the chains on the windlasses. He
took an impression of the lock of the trap-door, and when he went away
in the very early hours of the morning he understood the apparatus which
was intended to lower the car as well as any person who had managed
it. He knew nothing about the shaft under the great door, but this
he intended to investigate as thoroughly as he had investigated the
machinery.

The next night he entered the building very soon after Cunningham had
gone his rounds, and he immediately set to work to prepare for his
descent into the shaft. He disconnected one of the engines, for he
sneeringly said to himself that the other one was more than sufficient
to lower and raise the car. He charged and arranged all the batteries
and put in perfect working order the mechanism by which Clewe had
established a connection between the car and the engines, using one of
the chains as a conductor, so that he could himself check or start the
engines if an emergency should render it necessary.

Then Rovinski, bounding around like a wild animal in a cage, took out a
key he had brought with him, opened the trap-door, lifted it back, and
gazed down. He could see a beautifully cut well, but that was all. But
no matter how deep it was, he intended to go down to the bottom of it.

He started the engine and lowered the car to the ground. Then he looked
up at a grating which hung above it and determined to make use of this
protection. He could not lower it in the ordinary way after he had
entered the car, but in fifteen minutes he had arranged a pulley and
rope by which, after the car had gone below the surface, he could lower
the grating to its place. He got in, started down into the dark hole,
stopped the engine, lowered the grating, went down a little farther, and
turned on the electric lights.

The descent of Rovinski was a succession of the wildest sensations of
amazed delight. Stratum after stratum passed before his astonished
eyes, and, when he had gone down low enough, he allowed himself the most
extravagant expressions of ecstasy. His progress was not so regular and
steady as that of Roland Clewe had been. He found that h