alice <alice@xn.net> wrote in message news:<c08r2l$sgm$1@sparta.btinternet.com>...

Even in the 60's, the hammer and feather can be made to hit the ground 
at the same time either by using some photographic fakery (i believe 
technology existed) or by ensuring that the hammer was the same weight 
as the feather i.e. how do you know the hammer and the feather were 
authentic objects?

Have you ever read a physics book written since 1553? 

Chris Manteuffel