they opened a large window and let down a ladder, on which the
spirit ascended at their invitation.
Bearwarden and Ayrault immediately set about combining the
chemicals that were to produce the force necessary to repel them
from Saturn. Bubbles of hydrogen were given off from the lead
and zinc plates, and the viscous primary batteries quickly had
the wires passing through a vacuum at a white heat.
"I see you are nearly ready to start," said the spirit, "so I