"When we were in the river system off Brazil ... we had huge logs coming down at speed ... river was doing about 5 knots ... if one of those hit us..."
I was reminded of something I saw on the beach of eastern Long Island a few years ago. A large eight foot long log had washed up on the beach and was rolling around in the surf. It look like Mahogany or some other exotic tropical wood. As it rolled around in the surf I wondered how far it had journeyed before it landed on the beach. Perhaps as far away as Brazil.