The Washington times., 1925-10-19
GROWN
|NARTF|C|AL
LIGHT
Successful Experiments Made.
Flowers Blossom In
Record Time
By ARTHUR WILLIAMS
Vice President of New York Edison
Company

Company
For more than forty years,
thanks to the genius of Thomas
Alva Edison, electricity has been
used to light our homes, stores,
factories and Streets fact with
which everyone is familiar.
want to tell you, however, of a
most remarkable use for electric
light, which has been watched with
the utmost interest in scientific cir
cles because Of its far-reaching pos
sibilities, but of which little is
known by the public at large.
refer to the use of electric light to
stimulate plant growth.
That light is the most important
factor in nature, influencing plant
life. has long been known, and
that electric light, in some forms,
has the healing power of the sun
litself has been recognized by the
medical profession for some years.
But we have just begun to dis
lamp has also the life-giving quail
ties of the sun, at least so far as
the higher plants are concerned.
Light is absolutely essential for
the development of plant life, be-
cause only in the presence~of light
can plants take carbon from the
atmosphere and assimilate it. 1t
is this process that produces the
green color in leaves and in vege-
tables. That is why the growth of
plants is retarded during dark.
cloudy days and why we have
fewer and later crops in northern
regions, where sunlight is lower
in intensity and not so continuous.
IN EXPERIMENTAL STAGES
Although the use of artificial
light to stimulate the plant growth
is still in the experimental stages
enough has been accomplished to
warrant the prediction of scientists
that light may in few years be
supplied economically to the com
mercial grower of early vegetables
and flowers, thus making possible
more abundant supply of many
popular flowers and vegetables at
seasons of the year during which
they are at present rare. Some
of the most interesting experiments
along this line are being carried
out just a few miles from New
York city at the Boyce Thompson
Institute for Plant Research in
Yonkers, to which we are in
debted for these facts.
To study the growth of plants
under artificial light. two basement
rooms are used. Daylight has no
access to these rooms. One of them
is kept constantly dark and serves
as an artificial night. The other
room is Illuminated BY powerful
electric lights suspended from the
ceiling. Plants are exposed to this
artificial light for a number OF
hours each day, after which they
are put into the dark room In
which the 24-hour cycle of the day
is completed. 1t was found that
plants grown under these conditions
not only were healthy, bloomed and
produced seed. but that many OF
them bloomed earlier in artificial
light than similar plants grown I'M
der the best green house conditions
Among the latter were the gera'
mum, snapdragon, radish, sunflower
and sweet peas. Nasturtiums
grown under artificial light were
found to last longer than those
grown in natural light.
GROWN WITHOUT DAYLIGHT
The experiment. carried on in
4
trio light prove that plants car
| be grown without ever enjoying
daylight. Some very interesting
experiments were carried on to
find out what would happen If the
daylight were supplemented by
electric light at night. For those
experiments a large electrically
driven crane, from which are sus
pended forty-eight electric lights Of
900 watts each, about $4,000 can
die power, is moved at night ovel
the greenhouse. The lamps are
arranged SO that the investigator
can regulate the amount of light
used each night at his will. Some
remarkable results have been oh
tanned with the aid Of this appa
ratus.
1t was found that giving plants
| additional light after the sun went
down greatly fastened their
growth. Sweet peas bloomed fiv.
weeks earlier than they did II
daylight alone. A certain kind Of
| clover which under natural condi
tons takes two years to bloom
when given additional light bios
somed in q little over two months
Lettuce was grown from Seeding
to head, and seed produced in from