And then came the telephone, giving direct instantaneous communication and putting the people of each nation within hearing distance of each other.

It was the completion of a long series of inventions.

It was the keystone of the arch.

It was the one last improvement that enabled interdependent nations to handle themselves and to hold together.
To make railways and steamboats carry letters was much, in the evolution of the means of communication.

To make the electric wire carry signals was more, because of the instantaneous transmission of important news.
But to make the electric wire carry speech was MOST, because it put all fellow-citizens face to face, and made both message and answer instantaneous.