a stream 10 m. broad flowing from north to south, where we
had to halt, as my men said they were absolutely exhausted and could not
go another step. The water of that stream was simply delicious. We killed
a monkey, which my men ate eagerly for dinner.

On August 28th we left that stream at eight o'clock. We were confronted
by a succession of steep hills with vertical rocks of immense size, on
the summit of which were great slabs also of rock, not unlike angular
roofs of houses. It was most difficult, I confess, for my men to take the
loads up and down those giant rocks, especially as there were many fallen
trees among them and the rocks themselves were extremely slippery.

It would not do to repeat in these pages the language of my men as they
scrambled up and rolled down the numerous rocks--falling so clumsily that
they always managed to injure themselves more or less. I was sorry for my
loads, especially the instruments, which got knocked about in a pitiful
way.

We came across three distinct hill ranges of that type, over which we had
to travel, the highest point being some 300 ft. above the level of the
Tapajoz River. The last bit in particular of that hilly region was
diabolically steep, with loose rocks which gave us no end of trouble. A
beautiful little streamlet flowing east descended in cascades among those
huge rocks. Eventually we reached the summit of the plateau, a huge flat
expanse of dark red volcanic rock. My men were so tired that we had to
camp on that elevation. Nothing but a few shrubs grew in the interstices
of that great table of rock, which extended for several kilometres to the
north. The barrier of rock, a spur of the great central plateau, was very
interesting from a geological point of view.

On August 29th we again marched westward, cutting our way through the
forest, and found two streamlets--one flowing south, the other north.
Late in the afternoon we arrived at a spot where there was another great
mass of rock, most troublesome for us. My men were discontented, saying
that when they agreed to march through the forest they had not agreed to
march over rocks--as if I had placed these there on purpose to annoy
them. They were extremely morose. I knew by their manner that I had fresh
trouble in store.

In the centre of that second immense table of rock I found a few pools of
putrid rain-water in cavities. My men wanted to halt there, but I induced
them to march along in hopes of finding a