er than the Moon's, if the Earth's mountains bore
the same ratio to those of the Moon, Everest should be more than sixteen
miles high, whereas it is not quite six."

"How do the general heights of the Himalayahs compare with those of the
highest lunar mountains?" asked Ardan, wondering what would be his next
question.

"Fifteen peaks in the eastern or higher division of the Himalayahs, are
higher than the loftiest lunar peaks," replied Barbican. "Even in the
western, or lower section of the Himalayahs, some of the peaks exceed
_Doerfel_."

"Which are the chief lunar mountains that exceed Mont Blanc in
altitude?" asked Ardan, bravely suppressing a yawn.

"The following dozen, ranged, if my memory does not fail me, in the
exact order of their respective heights;" replied Barbican, never
wearied in answering such questions: "_Newton_, _Curtius_, _Casatus_,
_Rheita_, _Short_, _Huyghens_, _Biancanus_, _Tycho_, _Kircher_,
_Clavius_, _Endymion_, and _Catharina_."

"Now those not quite up to Mont Blanc?" asked Ardan, hardly knowing what
to say.

"Here they are, about half a dozen of them: _Moretus_, _Theophilus_,
_Harpalus_, _Eratosthenes_, _Werner_, and _Piccolomini_," answered
Barbican as ready as a schoolboy reciting his lesson, and pointing them
out on the map as quickly as a compositor distributing his type.

"The next in rank?" asked Ardan, astounded at his friend's wonderful
memory.

"The next in rank," replied Barbican promptly, "are those about the size
of the Matterhorn, that is to say about 2-3/4 miles in height. They are
_Macrobius_, _Delambre_, and _Conon_. Come," he added, seeing Ardan
hesitating and at a loss what other question to ask, "don't you want to
know what lunar mountains are about the same height as the Peak of
Teneriffe? or as AEtna? or as Mount Washington? You need not be afraid of
puzzling me. I studied up the subject thoroughly, and therefore know all
about it."

"Oh! I could listen to you with delight all day long!" cried Ardan,
enthusiastically, though with some embarrassment, for he felt a twinge
of conscience in acting so falsely towards his beloved friend. "The fact
is," he went on, "such a rational conversation as the present, on such
an absorbing subject, with such a perfect master--"

"The Sun!" cried M'Nicholl starting up and cheering. "He's cleared the
disc completely, and he's now himself again! Long life to him! Hurrah!"

"Hurrah!" cried the others quite as enthusiastically