How many U.F.O. sightings were reported before man entered the aviation age?

Answer 1

Lots. See the "Great Airship Flap" of the 19th century. In the old days people saw UFO's as mystery flying ships, demons, monsters, angels, etc. It's only recently we've started to talk about them as space aliens.

UFO's are really about our collective need to mythologize that which we do not understand.

Answer 2

Since the printing press was around about 150 years before airships, you'd think there would be some, besides shooting stars and comets if such things exist, but have never heard of any.