We were still wholly unable to tell where we were going or what lay ahead of us.  Round the camp-fire, after supper, we held endless discussions and hazarded all kinds of guesses on both subjects.  The river might bend sharply to the west and enter the Gy-Parana high up or low down, or go north to the Madeira, or bend eastward and enter the Tapajos, or fall into the Canuma and finally through one of its mouths enter the Amazon direct.  Lyra inclined to the first, and Colonel Rondon to the second, of these propositions.  We did not know whether we had one hundred or eight hundred kilometres to go, whether the stream would be fairly smooth or whether we would encounter waterfalls, or rapids, or even some big marsh or lake.  We could not tell whether or not we would meet hostile Indians, although no one of us ever went ten yards from camp without his rifle.  We had no idea how much time the trip would take.  We had entered a land of unknown possibilities.

We started down-stream again early in the afternoon of March 5.  Our hands and faces were swollen from the bites and stings of the insect pests at the sand-flat camp, and it was a pleasure once more to be in the middle of the river, where they did not come, in any numbers, while we were in motion.  The current was swift, but the river was so deep that there were no serious obstructions.  Twice we went down over slight riffles, which in the dry season were doubtless rapids; and once we struck a spot where many whirlpools marked the presence underneath of boulders which would have been above water had not the river been so swollen by the rains.  The distance we covered in a day going down-stream would have taken us a week if we had been going up.  The course wound hither and thither, sometimes in sigmoid curves; but the general direction was east of north.  As usual, it was very beautiful; and we never could tell what might appear around any curve.  In the forest that rose on either hand were tall rubber-trees.  The surveying canoes, as usual, went first, while I shepherded the two pairs of lashed cargo canoes.  I kept them always between me and the surveying canoes—­ahead of me until I passed the surveying canoes, then behind me until, after an hour or so, I had chosen a place to camp.  There was so much overflowed ground that it took us some little time this afternoon before we found a flat place high enough to be dry.  Just before reaching camp Cherrie shot a jacu, a handsome bird somewhat akin to, but much smaller than, a turkey; after Cherrie had taken its skin, its body made an excellent canja.  We saw parties of monkeys; and the false bellbirds uttered their ringing whistles in the dense timber around our tents.  The giant ants, an inch and a quarter long, were rather too plentiful around this camp; one stung Kermit; it was almost like the sting of a small scorpion, and pained severely for a couple of hours.  This half-day we made twelve kilometres.