Evening star., 1923-11-01
.NzTODAY'S SPOTLIGHT
BY PAUL Y. COLLINS

dark house about 4 o'clock each day
we simulate the shorter hours of a
later month and hasten the fruition,
which normally would have been de-
layed until that month Poinsettia
can be made to bloom in July. while
its normal time Is Christmas, simply
py cutting down the hours of it's sun
iight to November and December
length.
The ordinary cosmos regularly flow :
ers IN the fall, but not because the
cooler temperature Of autumn tells
IL tnat 1t is time to blossom. IL, suc-
cessiVe paintings Of cosmos are made
IN greenhouse during the late win
yer and early spring. with a uniform
iperature I'LL throughout. the plant
sn sngs made after certain date Will
ran to blossom the next fall. but viii
continue to grow till -sthe following
ran and then flower atSthe usual sea-
son. rms cannots~be attributed to
eenperature, nor instinct" but is
sunshine in the blooming season. No
other length Of the days sunshine
Will bring the bloom.
Inc cosmos requires short hours Of
nt nsnt Tor blooming. Two cosmos
pants may germinate on the same
DAY. and IL one be given supplement.
tary hours of electric light and the
otner given only the natural hours
&c ne sun, the latter will bloom in
its natural season, while the, nisnt
having the extra hours OF light viii viii
hsep ne on growing. without bloom. nm
III It's own hours of light per dav he
tut bIa aoWnfo the normal length in It's
~ mn month. Ii is the length,
nontraf .Is strength. of the light which
sunbeam has the power of 10000
ioo'-cahdies. That means that it is
as strong a light as 10000 candles
one foot distant from the objective
the distance be made two feet the
iight would be. one-fourth. $500
candiepower. II it be four. feet
distant. the light would be only 625
cahoiepower, even with the same
Siectric current as gave 10000 at a
uIs lance or one foot. But an cleo
80 iisnt is ~ per cent heat and 3
pr cent nght, so that to reproduce
would be a heat which would in
stantiy burn up any plant or any
other substance. The heat is some.
~nat modified in practice in light
water between the source and the
op1ectlve, but with electric luminosity
eQual to that of q sunbeam, the
Water would be turned to steam in
our atmosphere so modifies the heat
OF the sunbeam that its TO- 600 candle
power is screened out, and the COM
paratiyely heatless light when it
soh So It @i 9nf bbesstaIion ,sa is harmless
tute electric light for sunlight is an
impossibility. But somehow. when
electric light. even though compara-
lighted hours of the day. the plant
keeps on using the energy stored up
from the sun, during the day, much
rs fat animal may starve, yet not
oie' SO long as II has not used up
Its fatty accumulation.
DIR. Garner says. In his report in
the year book for 1920 of the De-
partment of Agriculture page 40O) :
within suitable limits OF tempera-
ture and other important factors in
plant growth. there would seem to
be no reason why almost any plant
may not be made to flower and fruit
at any season Of the year, and in any
lregion. BY shortening the daily
light period through the use of dark
chambers or lengthening it by means
,of artificial light. reproductive activ-
tiles may be induced almost at WILL
4
In plant life sex of the plant IS
an essential factor of fruition. DIR.
John II. Schafner of, the Ohio State
University. taking up the Garner
Allard light experiments, finds that
without the normal hours of light
the sexes of seed are reversed or
become mixed and weakened from
the pure sexes-which opens up
! another vista in scientific research
for the control of plant-seX.
-; So ~
Surely Solomon was talking with
out scientific knowledge when he de-
clarsd, that .H+he had searched all
things and had concluded: so there
is no new thing under the sun"
y" Copyright 1895, by Paul Y. Collins,