The next thing you feel is the sudden swirl of motion and you feel as if you're traveling along some kind of roller coaster ride, but is probably more appropriately a log slide as parts of the log you are in start to break off from the main body and you struggle to breathe as you swim upwards and grab hold of something rubbery that's somehow floating amongst the debris.  It's very dark and the only light that exists seems to be coming from the drainage points far up above.  The stench here is awful and after a while of floating on your safety raft you come to the terrible thought that what you're holding onto is actually somebody's used condom.  Looking around the edges of the sewers, you can see the occasional flicker of shadows and glinting eyes as some rats scurry past the banks.  Maybe it would be better to stay where you are, or maybe taking your chances with hungry rats would make you feel better as opposed to hugging a dirty condom.