The important facts are that they all involved different principles from those worked out by Bell and that none of them ever attained any practical importance.

Reis, in particular, never grasped the essential principles that ultimately made the telephone a reality.

His work occupies a place in telephone history only because certain financial interests, many years after his death, brought it to light in an attempt to discredit Bell's claim to priority as the inventor.

An investigator who seems to have grasped more clearly the basic idea was the distinguished American inventor Elisha Gray, already mentioned as the man who had succeeded in perfecting the "harmonic telegraph." On February 14, 1876, Gray filed a caveat in the United States Patent Office, setting forth pretty accurately the conception of the electric telephone.

The tragedy in Gray's work consists in the fact that, two hours before his caveat had been put in, Bell had filed his application for a patent on the completed instrument.
The champions of Bell and Gray may dispute the question of priority to their heart's content; the historic fact is that the telephone dates from a dramatic moment in the year 1876.