gher intensities of
illumination. Mankind chooses a dimly lighted room in which to rest and
to dream. A room intensely lighted by means of well-designed units which
are not glaring is comfortable but not conducive to quiet contemplation.
It is a place in which to be active. This is perhaps one of the factors
which makes for increased production under adequate lighting.

Civilization has just passed the threshold of the age of adequate
artificial lighting and only a small percentage of the industries have
increased their lighting standards commensurately to the possibilities
of the present time. If high-intensity artificial lighting was installed
in all the industries and a 15 per cent. increase in production
resulted, as tests appear to indicate, the increased production would be
equal to that of nearly two million workers. This great increase in
output is brought about by lighting at an insignificant increase in cost
but without the additional consumption of food or clothing. Besides this
increase in production there is the decrease in spoilage. The saving
possible in this respect through adequate lighting has been estimated
for the industries of this country at $100,000,000. If mankind is to
have conveniences and luxuries, efficiency in production must be
practised to the utmost and in the foregoing a proved means has been
discussed.

There are many other ways in which artificial light may serve in
increasing production. Man has found that eight hours of sleep is
sufficient to keep him fit for work if he has a sufficient amount of
recreation. Before the advent of artificial light the activities of the
primitive savage were halted by darkness. This may have been Nature's
intention, but civilized man has adapted himself to the changed
conditions brought about by efficient and adequate artificial light.
There appears to be no fundamental reason for not imposing an artificial
day upon plants, animals, chemical processes, etc.; and, in fact,
experiments are being prosecuted in these directions.

The hen, when permitted to follow her natural course, rises with the
sun and goes to roost at sunset. During the winter months she puts in
short days off the roost. It has been shown that an artificial day, made
by piecing out daylight by means of artificial light, might keep the hen
scratching and feeding longer, with an increased production of eggs as a
result. Many experiments of this character have been carried out, and
ther