A teeth-splitting wheep-wheep-wheep in my ear, and I know we’ve been painted. Instantly, a brilliant yellow-orange lance of light reaches out toward our boat from somewhere along the riverbank. I know what it is, and I was expecting it, but even so I just barely keep control of my sphincters. Probing out across the river toward us, making the water boil and spray where it touches, it looks for all the world like a "death-ray" from out of some bad sci-fi trideo.