"OG" wrote in message
...

NB Galileo died before Newton was born.
But apart from that, its the force that is proportional, not the
acceleration.

Yer right; Newton was born in 1627, the same year Galileo died.

The acceleration depends on the force and (inversely) on the
mass, so Galileo's experiment matches Newton's theory.
Acceleration depends inversely on mass?
Force=Mass x Acceleration ; Newton's Second Law
Force/Mass = Acceleration ; dividing both sides by mass
Thus your assertion holds.