Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1877-02-28
THE BLUE GLASS DECEPTION.

Scientific American.l
In our last issue we reviewed the
alleged capabilities of sunlight fit
cred through blue glass in causing
plants to grow, etc., and by refer
ence to numerous experiments, we
reached the conclusion that the
light transmitted through the vio-
let-blue glass is nothing more than
normal sunlight diminished in in
tensity. We propose in the follow
ing to finish our discussion by
examining into the effects of light
and darkness upon organisms.
And we may especially here recall
the fact that General Pleasonton
claims that not only does the blue
light stimulate growth, but that it
is a positive remedial agent for such
severe ailments as spinal meningi-
tie, nervous irritation and exhaus-
tion, rheumatism, hemorrhage of
the lungs, deafness, partial paraly-
sis, shock due to severe confusion,
and others, of all of which he cites
cases.
The theory that various colored
lights exercise different effects on
the human system is an old one.
In 1881, DR.. Newbery of this city
asserted that yellow lightstimulates
the nervous, pink the nutritive,
and blue the locomotive tempera-
ment; and recently DR., Ponza, an
Italian physician, has asserted that
lunatics are greatly affected by
being placed in different colored
rooms. Red light, DR.. Ponza says,
removes feelings Of depression; blue
light induces calmness and by
violet light crazy person was in
one day cured.
1t is thoroughly demonstrated
fact that light is an important vital
stimulant, and that, if It's opera
tion be excluded, the development
of the healthy bodily structure is
arrested. Naturalists tell us that
in the absence of light the trans
formation Of a tadpole into a frog
is stopped, and the reptile remains
a tadpole. Plants in darkness be-.
come blanched and stunted in
growth; the process of fixing the
carbon in their tissues is arrested,
a modification Of the coloring prin-
ciple takes place, and they appear
white instead Of green. The sad
effects of deprivation of sunlight
are especially observable among
those who live in crowded alleys or
cellars, Or who work in mines,
where the light Of the sun seldom
or never penetrates. The total ex-
clusion of the SUMS beams ppos
duces an impoverished and diSor-
dered state of the blood, emacia-
tion, muscular debility, and the dis
eases due to imperfect nutrition,
On the other hand, it is known
that for certain purposes darkness
or shaded lisht is advantageous to
the bodily condition. Fowls, for
instance, can be fattened much
more rapidly in the dark, and it
would seem that the absence of
light exercises a very great inau-
ence over the power possessed by
feed in increasing the size of ami
mails. 1t likewise seems to exercise
a soothing and quieting influence,
increasing the disposition of ami
mails to take rest, making less food
necessary, and causing them to
store up more nutriment in the
form of fat or muscle. Now, if
the organism to be treated is sub
iected to light, all Of which ia fl
tered through blue violet glass, then,
as we have previously demonstrated,
it is in light which is considerably
shaded. And very probably to this
cause-and not at all to the pecu-
liar hue Of the Lights to be at
t-ibuted the quieting influence on
nervous and insane people which
DR.. Ponza has remarked.
But General Pleasanton does not
use blue-yiolet glass alone. On the
contrary, he employs a combination
of blue light and pure sunlight, the
latter very much preponderating.
In his grapery, for example, only