I found one of these on a road trip a long time ago. We were heading up the hill to Magazine Mountain in Arkansas in the rain. My old Chevy pickup was strugglin

I found one of these on a road trip a long time ago. We were heading up the hill to Magazine Mountain in Arkansas in the rain. My old Chevy pickup was struggling as if we were climbing and with all the twists in the road we couldn't go very fast. I was looking out the side window making sure I didn't find the ditch and we could plainly see that the water was flowing uphill from our frame of reference. The engine felt like we were climbing and the water was definitely moving in the apparent uphill direction. I filed that away in my memory as a curiosity. Thanks for the nice explanatory site. It is possible that the illusion persisted because our horizon was completely blocked by the mixed hardwood forest we were driving through. The old Chevy was a bit of a clunker. Top speed was just over 55 mph with that worn-out engine although the Missouri State Police with their "speed checked by airplanes" were gracious enough to give me (and a couple others with out of state plates) a ticket for 72 in a 55 as we reached the state police checkpoint just before we left Missouri. The old truck carried us to the beach in Charleston, SC and then back up through the Smokies and across Tennessee to our home in Texas. Cheap trip. When I got home I had just spent my last few dollars on gas and a loaf of bread for our peanut butter. It was a great way to celebrate graduating high school. Good times.