The mightiest river in the world is the Amazon.  It runs from west to east, from the sunset to the sunrise, from the Andes to the Atlantic.  The main stream flows almost along the equator, while the basin which contains its affluents extends many degrees north and south of the equator.  The gigantic equatorial river basin is filled with an immense forest, the largest in the world, with which no other forest can be compared save those of western Africa and Malaysia.  We were within the southern boundary of this great equatorial forest, on a river which was not merely unknown but unguessed at, no geographer having ever suspected its existence.  This river flowed northward toward the equator, but whither it would go, whether it would turn one way or another, the length of its course, where it would come out, the character of the stream itself, and the character of the dwellers along its banks—­all these things were yet to be discovered.

One morning while the canoes were being built Kermit and I walked a few kilometres down the river and surveyed the next rapids below.  The vast still forest was almost empty of life.  We found old Indian signs.  There were very few birds, and these in the tops of the tall trees.  We saw a recent tapir track; and under a cajazeira tree by the bank there were the tracks of capybaras which had been eating the fallen fruit.  This fruit is delicious and would make a valuable addition to our orchards.  The tree although tropical is hardy, thrives when domesticated, and propagates rapidly from shoots.  The Department of Agriculture should try whether it would not grow in southern California and Florida.  This was the tree from which the doctor’s family name was taken.  His parental grandfather, although of Portuguese blood, was an intensely patriotic Brazilian.  He was a very young man when the independence of Brazil was declared, and did not wish to keep the Portuguese family name; so he changed it to that of the fine Brazilian tree in question.  Such change of family names is common in Brazil.  Doctor Vital Brazil, the student of poisonous serpents, was given his name by his father, whose own family name was entirely different; and his brother’s name was again different.

There were tremendous downpours of rain, lasting for a couple of hours and accompanied by thunder and lightning.  But on the whole it seemed as if the rains were less heavy and continuous than they had been.  We all of us had to help in building the canoes now and then.  Kermit, accompanied by Antonio the Parecis and Joao, crossed the river and walked back to the little river that had entered from the east, so as to bring back a report of it to Colonel Rondon.  Lyra took observations, by the sun and by the stars.  We were in about latitude 11 degrees 2 minutes south, and due north of where we had started.  The river had wound so that we had gone two miles for every one we made northward.  Our progress had been very slow; and until we got out of the region of incessant rapids, with their attendant labor and hazard, it was not likely that we should go much faster.