communicated to the whole of the ball such a heat that it could not
be held in the hand."

In truth, I was beginning to be shaken by the Professor's arguments,
besides which he gave additional weight to them by his usual ardour
and fervent enthusiasm.

"You see, Axel," he added, "the condition of the terrestrial nucleus
has given rise to various hypotheses among geologists; there is no
proof at all for this internal heat; my opinion is that there is no
such thing, it cannot be; besides we shall see for ourselves, and,
like Arne Saknussemm, we shall know exactly what to hold as truth
concerning this grand question."

"Very well, we shall see," I replied, feeling myself carried off by
his contagious enthusiasm. "Yes, we shall see; that is, if it is
possible to see anything there."

"And why not? May we not depend upon electric phenomena to give us
light? May we not even expect light from the atmosphere, the pressure
of which may render it luminous as we approach the centre?"

"Yes, yes," said I; "that is possible, too."

"It is certain," exclaimed my uncle in a tone of triumph. "But
silence, do you hear me? silence upon the whole subject; and let no
one get before us in this design of discovering the centre of the
earth."