e appears to be a general conclusion that the use of artificial
light for this purpose is profitable.

Experiments conducted recently by the agricultural department of a large
university indicate that in poultry husbandry, when artificial light is
applied to the right kind of stock with correct methods of feeding, the
distribution of egg-production throughout the whole year can be
radically changed. The supply of eggs may be increased in autumn and
winter and decreased in spring and summer. Data on the amount of
illumination have not been published, but it is said that the most
satisfactory results have been obtained when the artificial illumination
is used from sunset until about 9 P. M. throughout the year.

An increase of 30 to 40 per cent. in the number of eggs laid on a
poultry-farm in England as the result of installing electric lamps in
the hen-houses was reported in 1913. On this farm there were nearly 200
yards of hen-houses containing about 6000 hens, and the runs were
lighted on dark mornings and early nights of the year preceding the
report. About 300 small lamps varying from 8 to 32 candle-power were
used in the houses. It was found that an imitation of sunset was
necessary by switching off the 32 candle-power lamps at 6 P. M.
and the 16 candle-power lamps at 9:30. This left only the 8
candle-power lamps burning, and in the faint illumination the hens
sought the roosting-places. At 10 P. M. the remaining lights
were extinguished. It was found that if all the lights were extinguished
suddenly the fowls went to sleep on the ground and thus became a prey to
parasites. The increase in production of eggs is brought about merely by
keeping the fowls awake longer. On the same farm the growth of chicks
incubated during the winter months increased by one third through the
use of electric light which kept them feeding longer.

Many fishermen will testify that artificial light seems to attract fish,
and various reports have been circulated regarding the efficacy of using
artificial light for this purpose on a commercial scale. One report
which bears the earmarks of authenticity is from Italy, where it is said
that electric lights were successfully used as "bait" to augment the
supply of fish during the war. The lamps were submerged to a
considerable depth and the fish were attracted in such large numbers
that the use of artificial light was profitable. The claims made were
that the supply of fish was not only increa