on
in undesired forms, the allowing valuable energy to do useless work? In
that amazing case of long distance transmission, common sunshine, a
solar beam arrives at the earth from the sun not one whit the weaker for
its excursion of 92,000,000 miles. It is highly probable that we are
surrounded by similar cases of the total absence of friction in the
phenomena of both physics and chemistry, and that art will come nearer
and nearer to nature in this immunity is assured when we see how many
steps in that direction have already been taken by the electrical
engineer. In a preceding page a brief account was given of the theory
that gases and vapours are in ceaseless motion. This motion suffers no
abatement from friction, and hence we may infer that the molecules
concerned are perfectly elastic. The opinion is gaining ground among
physicists that all the properties of matter, transparency, chemical
combinability, and the rest, are due to immanent motion in particular
orbits, with diverse velocities. If this be established, then these
motions also suffer no friction, and go on without resistance forever.

As the investigators in the vanguard of science discuss the constitution
of matter, and weave hypotheses more or less fruitful as to the
interplay of its forces, there is a growing faith that the day is at
hand when the tie between electricity and gravitation will be
unveiled--when the reason why matter has weight will cease to puzzle the
thinker. Who can tell what relief of man's estate may be bound up with
the ability to transform any phase of energy into any other without the
circuitous methods and serious losses of to-day! In the sphere of
economic progress one of the supreme advances was due to the invention
of money, the providing a medium for which any salable thing may be
exchanged, with which any purchasable thing may be bought. As soon as a
shell, or a hide, or a bit of metal was recognized as having universal
convertibility, all the delays and discounts of barter were at an end.
In the world of physics and chemistry the corresponding medium is
electricity; let it be produced as readily as it produces other modes of
motion, and human art will take a stride forward such as when Volta
disposed his zinc and silver discs together, or when Faraday set a
magnet moving around a copper wire.

For all that the electric current is not as yet produced as economically
as it should be, we do wrong if we regard it as an infant f