We now, having made up our minds to examine into this matter, sallied
forth eagerly in the direction of the waterspout rocks, which, as I have
before mentioned, were not far from our present place of abode. On
arriving there we hastened down to the edge of the rocks and gazed over
into the sea, where we observed the pale-green object still distinctly
visible, moving its tail slowly to and fro in the water.

"Most remarkable!" said Jack.

"Exceedingly curious!" said I.

"Beats everything!" said Peterkin.--"Now, Jack," he added, "you made
such a poor figure in your last attempt to stick that object that I
would advise you to let me try it. If it has got a heart at all, I'll
engage to send my spear right through the core of it; if it hasn't got a
heart, I'll send it through the spot where its heart ought to be."

"Fire away, then, my boy," replied Jack with a laugh.

Peterkin immediately took the spear, poised it for a second or two above
his head, then darted it like an arrow into the sea. Down it went
straight into the centre of the green object, passed quite through it,
and came up immediately afterwards, pure and unsullied, while the
mysterious tail moved quietly as before!

"Now," said Peterkin gravely, "that brute is a heartless monster; I'll
have nothing more to do with it."

"I'm pretty sure now," said Jack, "that it is merely a phosphoric light;
but I must say I'm puzzled at its staying always in that exact spot."

I also was much puzzled, and inclined to think with Jack that it must be
phosphoric light, of which luminous appearance we had seen much while on
our voyage to these seas. "But," said I, "there is nothing to hinder us
from diving down to it, now that we are sure it is not a shark."

"True," returned Jack, stripping off his clothes. "I'll go down, Ralph,
as I'm better at diving than you are.--Now, then, Peterkin, out o' the
road!" Jack stepped forward, joined his hands above his head, bent over
the rocks, and plunged into the sea. For a second or two the spray
caused by his dive hid him from view; then the water became still, and
we saw him swimming far down in the midst of the green object. Suddenly
he sank below it, and vanished altogether from our sight! We gazed
anxiously down at the spot where he had disappeared for nearly a minute,
expecting every moment to see him rise again for breath; but fully a
minute passed and still he did not reappear. Two minutes passed! and
then a flood