objects were dropped off the Eiffel tower
Is it possible to drop anything off the Eiffel tower without having it bounce off the side a couple of times?
Now the Tower of Pisa I could see working. But that could be too short to measure the effect of drag.
The formula for the terminal velocity of a falling object depends on its density (mass for identically sized objects).
Terminal velocity - Wikipedia, the free encyclopedia
So I would expect that, given sufficient altitude to allow terminal velocity to be approached and enough time for that difference in velocity to manifest itself as a noticeable difference in descent time, that difference would become apparant.