ater in one or two places. Sand covered the lava-flow which had
travelled northward. Quantities of heavy, spherical, bullet-like blocks
of hard-baked rock were scattered all about--evidently shot out of the
crater when active.

We had travelled 80 kil. from Cayambola in three days, and we had reached
a spot of slight, well-rounded undulations where grazing was fair. I
decided to halt early in the afternoon--more particularly as this spot
appeared to me to have been at one time or other submerged--probably it
had been a lake bottom. I had, since the beginning of my journey, been
searching everywhere for fossils--but in vain. I had not seen the
vestiges of a single one. Personally, I was persuaded that Central Brazil
could well be geologically classified in the archaic group--the most
ancient of the terrestrial crust, and consisting (in Brazil) chiefly of
gneiss, mica schists and granite, solidified into their present form by
intense eruptive phenomena and dissolved--not by immersion in ocean
waters, as some suppose, but by deluges of such potentiality as the human
mind can hardly conceive.

It was quite enough to visit the central plateau of Brazil to be
persuaded that that continent had never been submerged under a sea; on
the contrary, it must have been the oven of the world. The volcanic
activity which must have taken place in that part of the world--it was
not a separate continent in those days--was quite, as I have said, beyond
human conception. This does not mean that at later periods there may not
have been temporary lakes--as, for instance, in the spot where we
encamped that night--or portions of country which had become flooded,
upon the cooling of the earth, and subsequently became drained and dry
again.

A wonderful surprise awaited me that day. To the north of my camp was a
peculiar round mound. I climbed it, and what was my astonishment in the
short ascent to find near the summit, among a lot of lava pellets, marble
fragments, crystals, and great lumps of iron ore, a number of vertebrae
from the tail and spine of a giant reptile! The vertebrae had been
disjointed and scattered somewhat about by wind and water--but there they
were; the smaller ones on the side of the hill, the larger on the
summit--which led me to believe that the animal had crouched on the top
of the hill when dying. Some of the fossil vertebrae were so large and
heavy that I hardly had the strength to lift them up. The
bones--petrified--