utters
itself to the ear, and man's book blinds the eyes and overheats the
imagination. Nature's method is to teach by the ear, and to reserve
the sight for the discovery and enjoyment of beauty.

The sound-book in some form is coming; and with that the intellectual
repose of mankind will begin to be restored. The use of the eye for
the offices of education instead of the stronger ear, has, we think,
impaired, if it has not destroyed, the equilibrium of the human mind.
That equilibrium must be restored. The mental diseases and unrest of
our race are largely attributable to the over-excitement of the
faculties through ages of too much seeing.

The Age of Hearing is, we think, to be ushered in with the twentieth
century. The coming of that age will tend to restore the mental
balance of mankind. Memory, now almost obliterated, will come again.
The over-heated perceptions will cool. The imagination will become
calm, and the eye itself will recover, we hope, from the injuries, of
overstrain, and will regain its power and lustre. Man will see once
more as the eagle sees, and will learn Shakespeare by heart. He will
remember all knowledge, and will again be able to see, as of old, from
Sicily to Carthage!

THE EVOLUTION OF THE DYNAMO.

BY PROFESSOR JOSEPH P. NAYLOR, A.M.

It is difficult to estimate the influence in modifying and shaping the
nineteenth century civilization that has resulted from the discovery
of the dynamo and the production of heavy currents of electricity.
That it has had great influence is evident without question. The arc
light for out-of-doors lighting and the incandescent lamp for inside
has modified all our previous ideas of illumination. Effects in light
are now produced daily that were beyond imagination twenty years
since. The trolley and the electromoter have largely solved the
problem of rapid transit through our crowded cities. Thus larger
business facilities, suburban homes and cheaper living, cleanliness
and better sanitary conditions are electrical results.

The transmission of energy by the electric current from a central
plant makes possible many small industries that could not exist
without it, and gives employment and happiness to hundreds. The art of
Electro-metallurgy seems but the development of months: yet it already
employs millions of capital and is adding thousands daily to the
world's wealth. Steam and wind and tide contribute to the work. Even
Niagara is being touched by