The Dutch spectacle-maker, Hans Lippershey
publically demonstrates his new invention,
the "spyglass" [telescope] before the Dutch
Parliament in Hague.

Alas, his demonstration did not result
in him receiving a patent for it.

He did however receive orders to purchase his "spyglasses"
in the coming years..
His 'invention' revolutionized these areas of human activity
over the next 400 years:
Astronomy.
Espionage.
Law-enforcement surveillance.
Military tactics.
Zoology.
Surveying & geodetics [with telescopic apparatus].
Maritime commerce.
Exploration.
Seafaring.
Bird-watching hobby [binoculars evolved from telescopes]
Navigation.
Optics.
Photography [telephoto lenses also evolved from the telescope]
Physics.
Search and rescue.
etc...