--offered to help me make my trip of much
more consequence than I had originally intended. He has taken a keen
interest in the exploration and development of the interior of Brazil,
and he believed that my expedition could be used as a means toward
spreading abroad a more general knowledge of the country. He told me
that he would co-operate with me in every way if I cared to undertake
the leadership of a serious expedition into the unexplored portion of
western Matto Grosso, and to attempt the descent of a river which
flowed nobody knew whither, but which the best-informed men believed
would prove to be a very big river, utterly unknown to geographers. I
eagerly and gladly accepted, for I felt that with such help the trip
could be made of much scientific value, and that a substantial
addition could be made to the geographical knowledge of one of the
least-known parts of South America. Accordingly, it was arranged that
Colonel Rondon and some assistants and scientists should meet me at or
below Corumba, and that we should attempt the descent of the river, of
which they had already come across the headwaters.

I had to travel through Brazil, Uruguay, the Argentine, and Chile for
six weeks to fulfil my speaking engagements. Fiala, Cherrie, Miller,
and Sigg left me at Rio, continuing to Buenos Aires in the boat in
which we had all come down from New York. From Buenos Aires they went
up the Paraguay to Corumba, where they awaited me. The two naturalists
went first, to do all the collecting that was possible; Fiala and Sigg
travelled more leisurely, with the heavy baggage.

Before I followed them I witnessed an incident worthy of note from the
standpoint of a naturalist, and of possible importance to us because
of the trip we were about to take. South America, even more than
Australia and Africa, and almost as much as India, is a country of
poisonous snakes. As in India, although not to the same degree, these
snakes are responsible for a very serious mortality among human
beings. One of the most interesting evidences of the modern advance in
Brazil is the establishment near Sao Paulo of an institution
especially for the study of these poisonous snakes, so as to secure
antidotes to the poison and to develop enemies to the snakes
themselves. We wished to take into the interior with us some bottles
of the anti-venom serum, for on such an expedition there is always a
certain danger from snakes. On one of his trips Cherrie had lo