When one door closes, another opens; but we often look so long and so regretfully upon the closed door that we do not see the one which has opened for us.

Don't keep forever on the public road, going only where others have gone and following one after the other like a flock of sheep. Leave the beaten track occasionally and dive into the woods.

Great discoveries and improvements invariably involve the cooperation of many minds.

One day every major city in America will have a telephone.

America is a country of inventors, and the greatest of inventors are the newspaper men.

The nation that secures control of the air will ultimately control the world.

The great advantage [the telephone] possesses over every other form of electrical apparatus consists in the fact that it requires no skill to operate the instrument.