America. Again and
again these horrible creatures came writhing and springing towards us
across the surface of this putrid bog, and it was only by keeping our
shot-guns for ever ready that we could feel safe from them. One
funnel-shaped depression in the morass, of a livid green in color from
some lichen which festered in it, will always remain as a nightmare
memory in my mind. It seems to have been a special nest of these
vermins, and the slopes were alive with them, all writhing in our
direction, for it is a peculiarity of the Jaracaca that he will always
attack man at first sight. There were too many for us to shoot, so we
fairly took to our heels and ran until we were exhausted. I shall
always remember as we looked back how far behind we could see the heads
and necks of our horrible pursuers rising and falling amid the reeds.
Jaracaca Swamp we named it in the map which we are constructing.

The cliffs upon the farther side had lost their ruddy tint, being
chocolate-brown in color; the vegetation was more scattered along the
top of them, and they had sunk to three or four hundred feet in height,
but in no place did we find any point where they could be ascended. If
anything, they were more impossible than at the first point where we
had met them. Their absolute steepness is indicated in the photograph
which I took over the stony desert.

"Surely," said I, as we discussed the situation, "the rain must find
its way down somehow. There are bound to be water-channels in the
rocks."

"Our young friend has glimpses of lucidity," said Professor Challenger,
patting me upon the shoulder.

"The rain must go somewhere," I repeated.

"He keeps a firm grip upon actuality. The only drawback is that we
have conclusively proved by ocular demonstration that there are no
water channels down the rocks."

"Where, then, does it go?" I persisted.

"I think it may be fairly assumed that if it does not come outwards it
must run inwards."

"Then there is a lake in the center."

"So I should suppose."

"It is more than likely that the lake may be an old crater," said
Summerlee. "The whole formation is, of course, highly volcanic. But,
however that may be, I should expect to find the surface of the plateau
slope inwards with a considerable sheet of water in the center, which
may drain off, by some subterranean channel, into the marshes of the
Jaracaca Swamp."

"Or evaporation might preserve an equilibrium," remarked