o understand whence this earthy matter (twenty or thirty
per cent) comes. Throughout the neighborhood the ground is full, to
the depth of hundreds of feet, of coaly and asphaltic matter. Layers
of sandstone or of shale containing this decayed vegetable alternate
with layers which contain none; and if, as seems probable, the coaly
matter is continually changing into asphalt and oil, and then working
its way upward through every crack and pore, to escape from the
enormous pressure of the superincumbent soil, it must needs carry up
with it innumerable particles of the soils through which it passes.

In five minutes we had seen, handled, and smelt enough to satisfy us
with this very odd and very nasty vagary of tropic nature; and as we
did not wish to become faint and ill between the sulphureted hydrogen
and the blaze of the sun reflected off the hot black pitch, we hurried
on over the water-furrows, and through the sedge-beds to the farther
shore--to find ourselves, in a single step, out of an Inferno into a
Paradise.

[Illustration]

A STALAGMITE CAVE

(FROM THE VOYAGE OF THE CHALLENGER.)

BY SIR C. WYVILLE THOMSON, KT., LL.D., ETC.

[Illustration]

I think the Painter's Vale cave is the prettiest of the whole. The
opening is not very large. It is an arch over a great mass of debris
forming a steep slope into the cave, as if part of the roof of the
vault had suddenly fallen in. At the foot of the bank of debris one
can barely see in the dim light the deep clear water lying perfectly
still and reflecting the roof and margin like a mirror. We clambered
down the slope, and as the eye became more accustomed to the obscurity
the lake stretched further back. There was a crazy little punt moored
to the shore, and after lighting candles Captain Nares rowed the
Governor back into the darkness, the candles throwing a dim light for
a time--while the voices became more hollow and distant--upon the
surface of the water and the vault of stalactite, and finally passing
back as mere specks into the silence.

[Illustration: A GUIDE.]

After landing the Governor on the opposite side, Captain Nares
returned for me, and we rowed round the weird little lake. It was
certainly very curious and beautiful; evidently a huge cavity out of
which the calcareous sand had been washed or dissolved, and whose
walls, still to a certain extent permeable, had been hardened and
petrified by the constant percolation of water charged with c