d on the point of land between the two rivers. It was
extraordinary to realize that here about the eleventh degree we were
on such a big river, utterly unknown to the cartographers and not
indicated by even a hint on any map. We named this big tributary Rio
Cardozo, after a gallant officer of the commission who had died of
beriberi just as our expedition began. We spent a day at this spot,
determining our exact position by the sun, and afterward by the stars,
and sending on two men to explore the rapids in advance. They returned
with the news that there were big cataracts in them, and that they
would form an obstacle to our progress. They had also caught a huge
iluroid fish, which furnished an excellent meal for everybody in camp.
This evening at sunset the view across the broad river, from our camp
where the two rivers joined, was very lovely; and for the first time
we had an open space in front of and above us, so that after nightfall
the stars, and the great waxing moon, were glorious over-head, and
against the rocks in midstream the broken water gleamed like tossing
silver.

The huge catfish which the men had caught was over three feet and a
half long, with the usual enormous head, out of all proportions to the
body, and the enormous mouth, out of all proportion to the head. Such
fish, although their teeth are small, swallow very large prey. This
one contained the nearly digested remains of a monkey. Probably the
monkey had been seized while drinking from the end of a branch; and
once engulfed in that yawning cavern there was no escape. We Americans
were astounded at the idea of a catfish making prey of a monkey; but
our Brazilian friends told us that in the lower Madeira and the part
of the Amazon near its mouth there is a still more gigantic catfish
which in similar fashion occasionally makes prey of man. This is a
grayish-white fish over nine feet long, with the usual
disproportionately large head and gaping mouth, with a circle of small
teeth; for the engulfing mouth itself is the danger, not the teeth. It
is called the piraiba--pronounced in four syllables. While stationed
at the small city of Itacoatiara, on the Amazon, at the mouth of the
Madeira, the doctor had seen one of these monsters which had been
killed by the two men it had attacked. They were fishing in a canoe
when it rose from the bottom--for it is a ground fish--and raising
itself half out of the water lunged over the edge of the canoe at
them, w