Looking back, I should have pointed out that 1) the people group is asking for missionaries, and 2) translating the Bible and other materials into their language has the effect of preserving it.
The most uncomfortable thing was when it started to rain later that afternoon. E thought it was funny that I was perched on my bench shivering, and made a comment about my lack of an insulating fat layer. Suddenly, we came upon a stopped canoe with 3 Maki men and a couple of teenage boys in it. One of the boys insistently wanted us to stop, using exaggerated hand motions and saying the few Portuguese words he knew. "Drunk" and "angry" were two words I remember him saying, while pointing at the men in the back of the canoe. The boys boarded our canoe and told us to get out of there, so we took them back to their village through the pouring rain. The vocal boy showed me to the house in the picture below and asked, "You mission?" I said yes. Then we unloaded all the stuff from our canoe, including fuel. The Maki are known for stealing just about anything and seem particularly interested in anything that can get them drunk. I've heard they even have a way to use gasoline for that (it's 25% alcohol here).
It was wonderful to put on dry clothes. We talked with the people for a while and then made our supper and got our hammocks ready. We used mosquito nets too, since the region has malaria. As we lay in our hammocks, we could hear some people singing eerily not far from the house. Our guide said he was going to drink the cipó (Portuguese for vine, a drink that is supposed to give them visions). Someday we will have a better idea of what they do in the ceremony and what they believe about it, but right now we only have assumptions.
We returned to Basetown until we could find a guide who knew the way to some villages on another river. A couple of days later, we found someone and he took us to the villages on his river.