St. Landry democrat., 1881-10-15
SCIENTIFIC MISCELLANY.

-Abernethy used to say that "of the large
quantity of food a man swallows one fourth
supports him, and the rest he keeps at his risk.
A method Of improving India rubber and
gutta percha by the addition of distillate OF
birch-bark has lately been brought out. Distil
lation of the outer layers of the bark produces
dense, black, gummy matter resembling gut
"a percha and capable of resisting the action OF
air and of the strongest corrosive acids. 1t is
claimed that the durability Of India rubber or
sutta percha is greatly increased by the addi-
ton of a small quantity-a twentieth part is
sufficient-of the birch-barck gum.
M. Decourneau attributes the cracks in
common mOrtars and cements to the uncom-
bined quicklime which they contain. In order
10 neutralize the lime, he uses a very fine sill
ceous powder mixed with diluted nitric acid.
He thus obtains mortars of much greater more
Uniform and more lasting resistance than those
hitherto used The application of this method
has given excellent results. Stone made by the
process may be worked like the natural pro-
duct.
M. Gley, French Psychologist, has been in
restigating the effects of brain work on the
circulation OF the blood. In his experiments
he has found that when he applied himself to a
difficult subject, upon which he had to concen-
trate all his energies, the rythm of the heart
was far more accelerated than when consider
ing some matter with which he was familiar.
"A peculiar phenomenon occurred in August
on mountain Of Rhenish Prussia. In the
side Of the Brennende Berg pit of about
hundred square yards in area suddenly opened
emitting great volume of fame
and enguling house aud its inmates
It is believed that the cause of the catastrophe
was the ignition of gas rising from petroleum
vein in the depths of the mountain.
Paper betting is now being used in Japan,
and it is said to have been found stronger than
leather betting.
Sir John Lubbock estimates that 100000
animal species have existed on our globe, Of
which only about % 900 are as yet on record.
Heplaces the number of recent species at 7OO,-
600.
Experiments to determine the changes of
color produced in flowers by ammonia have
given these results: Over a dish of ammonia
was inverted funnel, in the tube of which
were placed the flowers experimental upon
Blue, violet and purple flowers were found to
change to beautiful green; deep red flowers
to black, and white to yellow. These changes
are most striking when the flowers have seve-
raj different tints, in which the red lines are
turned dark, the white yellow, etc. If the
flowers thus changed are placed in pure water
they retain their cOlors for several hours grad
ually resuming their original tints after that
time. Another observation made in this con-
nection is that the flowers Of the aster, which
are naturally inodorous, acquire a very agreea-
bic perfume under the influence of ammonia.
The sense of touch in eyeless fishes is shown
by experiment to be extraordinarily developed.
ton to two cases in which the Introduction OF
pllocarpin-the active principle of the powerful
Brazilian drug, jaborandi-into the human sys-
TEN has caused a very marked change in the |
color of the hair. In the first case the pilocar-
pin was administered at intervals during a |
period OF ten weeks with the object of "sweat- |
ing" the patient. In a few days after the first |
application the patients hair originally very
light was observed to be growing darker and |
III six months it had become almost pure black |
In the second case the hair had become percep- /
tlbly darker in week after treatment with pi- |
locarpin was commenced The patient in the first |
case was young lady Of twenty -five and the /
other was an infant. The introduction of labor
andi into medicine is of so recent date that lit
tie opportunity has been afforded for studying
it's varied action on the system, but there ap.
pears reason to believe that the color of the hair
is due to an oily pigment which Is increased
under the influence of the drug
During last winter the experiments of Mr.
C. w. Siemens on the action of electric light on
vegetation-with results which he has just des-
cribed to the British Science Association-were
continued. He noticed the curious fact that
plants exposed to the direct rays of the electric
arc soon become sickly and withered, while in
the light of the arc enclosed in glass globe
the vegetation d0urished to as remarkable ex-
tent as in his previous experiments. The IN
favorable action of the open arc is supposed to
arise from certain non-luminous rays which are
intercepted by the glass;. The botanist has
here subject for study.
Our friend W. n. scanland, OF the Bossier
Banner, mas as it were, taken the words out Of !
our mouth by publishing the following:
A MISTAKEN NOTION.-Thare are a consider
able number of persons who have very little, if
dao nff In - 1-1~1