were moving on converging lines, the curve on which they had
entered having swung them to the side nearest the earth; but they
saw that their own tremendous and increasing speed would carry
them in front of the moon in its nearly circular orbit. Wishing
to change the direction of their flight by the moon's attraction,
they shut off the power driving them from the earth, whereupon
the Callisto turned its heavy base towards the moon. They were
already moving at such speed that their momentum alone would
carry them hundreds of thousands of miles into space, and were
then almost abreast of the earth's satellite, which was but a few
thousand miles away. The spectacle was magnificent. As they
looked at it through their field glasses or with the unaided eye,
the great cracks and craters showed with the utmost clearness,
sweeping past them almost as the landscape flies past a railway
train. There was something awe-inspiring in the vast antiquity
of that furrowed lunar surface, by far the oldest thing that
mortal eye can see, since, while observing the ceaseless
political or geological changes on earth, the face of this dead
satellite, on account of the absence of air and water and
consequent erosion, has remained unchanged for bygone ages, as it
doubtless will for many more.

They closely watched the Callisto's course. At first it did not
seem to deflect from a straight line, and they stood ready to
turn on the apergetic force again, when the car very slowly began
to show the effect of the moon's near pull; but not till they had
so far passed it that the dark side was towards them were they
heading straight for Jupiter. Then they again turned on full
power and got a send-off shove on the moon and earth combined,
which increased their speed so rapidly that they felt they could