Davy, Gramme, Brush, Edison, and a host of other explorers in the new continents of science has so completely triumphed.  The ease, happiness, comfort, and welfare of mankind must be vastly multiplied, and the future must be reminded, in the glow that dispels the night, of that splendid fact that the progress of civilization depends, in a large measure, upon a knowledge of Nature’s laws, and the diffusion of that knowledge among the people.

THE TELEPHONE.

Perhaps no other great invention of man has been within so short a period so widely distributed as the telephone.  The use of the instrument is already co-extensive with civilization.  The cost at which the instruments are furnished is still so considerable that the poor of the world are not able to avail themselves of the invention; but in the so-called upper circles of society the use of the telephone is virtually universal.  It has made its way from the city to the town, from the town to the village, from the village to the hamlet, and even to the country-side where the millions dwell.

The telephone came by a speedy revelation.  It was born of that intense scientific activity which is the peculiarity of our age.  The antecedent knowledge out of which it sprang had existed in various forms for a long time.  The laws of acoustics were among the first to be investigated after a true physical science began to be taught.  The phenomena of sound are so universal and experimentation in sound production so easy, that the governing laws were readily discovered.

Acoustics, we think, foreran somewhat the science of heat, as the science of heat preceded that of light.  Electricity came last.  The telephone is an instrument belonging not wholly, not chiefly, but only in part, to acoustics.  It owes its existence to magnetic induction and electrical transmission as much as to the mere action of sound.  One foot of the instrument, so to speak, is acoustics, and the other foot electricity.  The telephone philosophically considered is an instrument for the conversion of a sound-wave into electrical motion, and its reconversion into sound at a distance.  The sound is, as it were, committed to the electrical current and is thus sent to the end of the journey, and there discharged with its message.  The possibility of this result lies first of all in the fact of electrical transmission by wire, and in the second place to the mounting of a sound-rider on the electrical saddle for an instantaneous journey with important despatches!

New results in scientific progress generally seem marvelous.  The unfamiliar and unexpected thing is always a marvel; but scientifically considered, the telephone does not seem so surprising as at first view.  The atmosphere is a conductor of sound.  It is the natural agent of transmission, and so far as the natural man is concerned, it is his only agent for the transmission of oral utterance.  If the unlearned man have his attention called to the surprising fact of hearing his fellow-man call out to him across a field or from far off on the prairie, he does not think it marvelous, but only natural.  Yet how strange it is that one human being can speak to another through the intervening space!