While this model is closer to reality than the original prediction, I still cannot help but think… How could they deviate from observations so strongly?
The trajectory where the object ends falling in a straight line is the observed trajectory for many objects, because air resistance slows them until forward motion is imperceptible. Cannonballs probably flew too quickly to be easily observed. The only person who knew that a cannonball was about to be fired and thus would be ready to watch it, would be standing at the cannon, and thus unable to perceive its trajectory in any case.
I agree, though, that if people played catch with balls, somebody watching from the side should have noticed that the ball never fell straight down at the end.
The trajectory where the object ends falling in a straight line is the observed trajectory for many objects, because air resistance slows them until forward motion is imperceptible. Cannonballs probably flew too quickly to be easily observed. The only person who knew that a cannonball was about to be fired and thus would be ready to watch it, would be standing at the cannon, and thus unable to perceive its trajectory in any case.
I agree, though, that if people played catch with balls, somebody watching from the side should have noticed that the ball never fell straight down at the end.