"Whats his name" was Galileo, and he performed his experiment from the Leaning Tower of Pisa. In fact, Galileos experiment was inconclusive to his observers. He dropped two canon balls of differing sizes, and there was a discernable difference in the time when they hit the ground. Galileo had not worked out the friction, but theorized that was to blame. His experment was repeated by Alan Shepard on the Moon with a feather and a tool, and in fact both objects fell at precisely the same speed.

Wing loading is not perfect, but it can generally tell you how a plane will fly.

Typical numbers for the 40-90 size planes are:
Sailplanes: 5-7 oz/sq. ft.
Trainers: 17-20 oz/sq. ft.
Sport aerobats: 20-24 oz/sq. ft.
Warbirds: 26-30 oz/sq. ft.

Cubic wing loading is a good way to determine across the scale how well a plane will fly. I'm not an expert on the theory, but it seems to work. Do a google search and you'll find lots of discussion.

My preference in the sport category is wing loading in the 23-24 oz/sq ft range. It suits my flying style well.

Brad