ng continuously. Enough mechanical power goes to waste on
the college campus to warm and light and supply all the
manufactories, street railroads and other consumers of
mechanical power in the city. How to harness this power and to
store it--that is the problem of the inventor and the engineer
of the twentieth century, a problem which in good time is sure
to be solved.

Who shall doubt, after finding this secret source of force in water,
that some future Watt is to discover other sources of power, or
perchance succeed in utilising the superabundant power known to exist in
the heat of the sun, or discover the secret of the latent force employed
by nature in animals, which converts chemical energy directly into the
dynamic form, giving much higher efficiencies than any thermo-dynamic
machine has to-day or probably ever can have. Little knew Shakespeare of
man's perfect power of motion which utilises all energy! How came he
then to exclaim "What a piece of work is man; how infinite in faculty;
in form and _moving_ how express and admirable"? This query, and a
thousand others, have arisen; for we forget Arnold's lines to the
Master:

"Others abide our question. Thou art free.
We ask and ask--thou smilest and art still."

Man's "moving" is found more "express and admirable" than that of the
most perfect machine or adaptation of natural forces yet devised. Lord
Kelvin says the animal motor more closely resembles an electro-magnetic
engine than a heat engine, but very probably the chemical forces in
animals produce the external mechanical effects through electricity and
do not act as a thermo-dynamic engine.

The wastage of heat energy under present methods is appalling. About 65
per cent. of the heat energy of coal can be put into the steam boiler,
and from this only 15 per cent. of mechanical power is obtained. Thus
about nine-tenths of the original heat in coal is wasted. Proceeding
further and putting mechanical power into electricity, only from 2 to 5
per cent. is turned into light; or, in other words, from coal to light
we get on an average only about one-half of 1 per cent. of the original
energy, a wastage of ninety-nine and one-half of every hundred pounds of
coal used. The very best possible with largest and best machinery is a
little more than one pound from every hundred consumed.

When Watt gave to the steam-engine five times its efficiency by
utilising the latent heat, he onl