l working at the door. Graham turned to the ladder again,
and was thrust by his conductor and helped up by those above, and then
he was standing on something hard and cold and slippery outside the
ventilating funnel.

He shivered. He was aware of a great difference in the temperature. Half
a dozen men stood about him, and light flakes of snow touched hands and
face and melted. For a moment it was dark, then for a flash a ghastly
violet white, and then everything was dark again.

He saw he had come out upon the roof of the vast city structure which had
replaced the miscellaneous houses, streets and open spaces of Victorian
London. The place upon which he stood was level, with huge serpentine
cables lying athwart it in every direction. The circular wheels of a
number of windmills loomed indistinct and gigantic through the darkness
and snowfall, and roared with a varying loudness as the fitful wind rose
and fell. Some way off an intermittent white light smote up from below,
touched the snow eddies with a transient glitter, and made an evanescent
spectre in the night; and here and there, low down, some vaguely outlined
wind-driven mechanism flickered with livid sparks.

All this he appreciated in a fragmentary manner as his rescuers stood
about him. Someone threw a thick soft cloak of fur-like texture about
him, and fastened it by buckled straps at waist and shoulders. Things
were said briefly, decisively. Someone thrust him forward.

Before his mind was yet clear a dark shape gripped his arm. "This way,"
said this shape, urging him along, and pointed Graham across the flat
roof in the direction of a dim semicircular haze of light. Graham obeyed.

"Mind!" said a voice, as Graham stumbled against a cable. "Between them
and not across them," said the voice. And, "We must hurry."

"Where are the people?" said Graham. "The people you said awaited me?"

The stranger did not answer. He left Graham's arm as the path grew
narrower, and led the way with rapid strides. Graham followed blindly. In
a minute he found himself running. "Are the others coming?" he panted,
but received no reply. His companion glanced back and ran on. They came
to a sort of pathway of open metal-work, transverse to the direction they
had come, and they turned aside to follow this. Graham looked back, but
the snowstorm had hidden the others.

"Come on!" said his guide. Running now, they drew near a little windmill
spinning high in the air. "Stoop," sai