a difference
distance makes! This little thing is only a trifle larger than our Moon,
and it's hiding everything else."

As she was speaking the full-orbed disc of Calisto, measuring nearly
three thousand miles across, swept between them and the planet. It shone
with a clear, somewhat reddish light like that of Mars. The _Astronef_
was feeling his attraction strongly, and Redgrave went to the levers and
turned on about a fifth of the R. Force to avoid too sudden contact with
it.

"Another dead world!" said Redgrave, as the surface of Calisto revolved
swiftly beneath them, "or at any rate a dying one. There must be an
atmosphere of some sort, or else that snow and ice wouldn't be there,
and everything would be either black or white as it was on the Moon. We
may as well land, however, and get a specimen of the rocks and soil to
add to the museum, though I don't expect there will be very much to see
in the way of life."

In another hour or so the _Astronef_ had dropped gently on to the
surface of Calisto at the foot of a range of mountains crowded with
jagged and splintery peaks, and a mile or two from the edge of a sea of
snow and ice which stretched away in a vast expanse of rugged frozen
billows beyond the horizon. Redgrave, as usual, went into the
air-chamber and tried the atmosphere. A second's experience of it was
enough for him. It was unbreathably thin and unbearably cold, although,
when mixed with the air of the _Astronef_, it distinctly freshened it
up. This proved that its composition was, or had been, fit for human
respiration.

"There's only one fault about it," he said, when he rejoined Zaidie in
the sitting-room. "You know what the schoolboy said when he started
kissing his first sweetheart, 'It takes too long to get enough of it.'"

"You seem to be very fond of referring to that particular subject,
Lenox."

"Well, yes; to tell you the truth I am," and then he referred to it
again in another form.

After this they went and put on their breathing-dresses and went for a
welcome stroll along the arid shores of the frozen sea after their
lengthy confinement to the decks of the _Astronef_. The Sun was still
powerful enough to keep them comfortably warm in their dresses, and
there was enough atmosphere to make this warmth diffused instead of
direct. So they were able to step out briskly, and every now and then
open their visors a little and take in a breath or two of the thin,
sharp air, which they found