Empirical Earth · Rotation & How We Measure It
The claim
“On a spinning ball rivers would flow uphill, or reverse direction several times a day.”
What is measured
A river follows gravity to the sea, and a spinning planet carries water, bed and banks together, so rivers run one steady way, downhill, no matter which compass direction that is.
What would show this is wrong
any inland river, far from the tidal reach, observed to reverse its flow on a daily cycle, or any river found to climb in elevation along its course.
Sources
This is one card from Empirical Earth, a free reference that states each flat-Earth claim at its strongest and then answers it with sourced measurements. Nothing is for sale and there are no advertisements.