He listened closely in hope of hearing a spoken word. Also, he tried
his best to make his agent look around the place. Other people might
be within sight. However, for a couple of minutes the oddly familiar
hands kept manipulating the unfamiliar instruments.

Then, somewhere quite close at hand, a deep-toned gong sounded a
single stroke. Instantly the agent looked up; and Smith saw that he
was inspecting the interior of a large engine-room. He had time to
note the huge bulk of a horizontal cylinder, perhaps fifty feet in
diameter, in the immediate background; also a variety of other
mechanisms, more like immensely enlarged editions of laboratory
apparatus than ordinary engines. Smith looked in vain for the
compact form of a dynamo or motor, and listened in vain for the
sound of either. Then, in swift succession, came two strokes on the
unseen gong, followed by a shrill whistle.

Smith's borrowed eyes became fixed upon that group of dials again.
Their indicators began to shift, some rapidly, some slowly. Once the
agent gave a swift glance through a round window--the place seemed
to be lighted by ordinary daylight--and Smith saw something
unrecognizable flit by.

A little further progress, and then came three strokes on the gong,
followed by a low thrumming. In response to these, the agent
deliberately picked out two levers, and pulled them down. When his
glance returned to the dials, one of them showed immense
acceleration.

By and by came another triple clanging, another pair of levers was