The citizen. (Frederick City, Md.) 1895-1923, 1897-04-09
written for the Citizen

A large Dussand microphonograph,
now being constructed for the Paris
exhibition of 1900, is expected to make
the voice be heard by 10000 people.
This form of apparatus is especially de-
signed for the deaf. and for the study
of the feeble sounds given out by the
body in health aud disease. 1t magni-
fies the voice much as lens magnifies
objects to the eye. The register is a
modified photograph, with dia-
phragm vibrated by small electro
magnets receiving currents through a
microphone; the repeater is somewhat
similar, with a microphone attached
to the membrane, the current for this
being obtained from one to sixty bat
terry cells and thence passing to tel
ephone. The intensity depends on the
amount Of current passing. The in
strument is being used in the educa-
ton of deaf-mutes, and has had a
marked effect in stimulating the nerves
and apparatus of hearing
Remarkable changes in the color of
fishes when asleep have been recorded
by Mr.. A. L. Verril. The most com
mon is a general darkening of the
dark spots or stripes, as was noticed
in various founders, minnows. the
black sea bass, the sea robins, the king
fish, and other species. This change
make the animal less conspicuous to
its enemies. Still more striking is the
alteration of the pattern of coloration,
as IN the common soup or pnrgy,
which in activity is of beautiful Sill
very color with bright iridescence, but
asleep is of dull, bronzy tint aud
crossed by about six dark bands. The
sleeping fishes take strange positions.
The file fishes often lean up obliuuely
against the glass of the aquaria with
the belly on tue bottom; and the tau
tog commonly sleeps on one side, of
ten partly buried in sand or gravel.
Though the kitchen garden lacks its
old-time medicinal herbs, the use of
these plants is said to be twice as great
as half a century ago. Professional
growers furnish the supply, aud the
Wholesale botanic druggist carries in
STOCK 1000 to 1900 different plants.
the minerals used being few. Wild
HERDS from New England are preferred
to The same plants from any other re-
giOu.
Anti-cholera vaccination originated
about twelve years ago with pr. Fer
ran, Spanish physician. His vac
cine OF eight drops OF a cholera culture
mixed with bile Was used with many
mlsforIunes upon $500 persons, but
gave sufficient encouragement 10 lead
hanklne's experiments, which have
proven successful IN India. Haffkine
employs attenuated cholera baciIli.
followed few days later by virulent
cultures. Equally good results from
the Use OF dead cholera baci lli-kiIled
by either heat or chloroform-are now
claimed by kolle, VINO gels the same
effects by simply using somewhat
larger doses of his less terrifying pre-.
ventlve. Comparative tests have
shown that the blood of the vaccinat-
ed individuals is 200 times as potent in
resisting cholera Infection as that of the
unvacclnated. As evidence of the ef-
fsctlveness of modern methods of deal
ing with cholera, the fact is mentioned
that it has had 500, 900 victims in Rus
STA since 1862, while in Germany-in-
GLIDING the Hamburg epidemic-its
deaths have been but 5000. The dis
ease seems destined soon to become as
obsolete as smallpox.
extraordinary power is claimed for
the pew signaling light of Col. Mlklas.
hevski, of the Russian Engineers. Its
signals have been read at distance OF
81 miles, and ii is hoped that the dis
lance may be increased to nearly so
miles by the use of rejecting mirrors.
The light is produced by spirit, which
Is coiored by red aud a green powder
of secret composition. The lantern en-
braces two tubes ending with pear
shaped balls, which on being pressed
emit respectively brilliant red aud
green flashes, by which the signals are
transmitted. The apparatus weighs
only seven pounds.
The Aurora Australis is found by DR..
Wilhelm Boiler, of Strasburg, from a
study of all published observations, to
have been most frequently seen in
March and October, and LEAST often in
June aud November. The frequency
seems TO vary, like that Of the Aurora
Borealis, in agreement with the eleven
Year sun-spo, period.
-
The birth rate in France has de-
creased from IS per 1000 at the begin
ming of the century TO -; and in 1885
the population showed u decrease of
1900. The birth rate is diminishing
in the United States as well as in the
European countries, having dropped
from $685. in 1880 to 26.6s in 1890.
English entomologists are becoming
alarmed at the rapid disappearance Of
the insects of the woods and fields.
Tie Leicester Literary aud Philosophi-
cal Society has drawn up series o.
regulations TO protect the insects from
the greed of collectors, and requires
that no specimen Of the Wood White
butterfly shall be taken. while Of Ger
tain other species collecto. may take
but a single specimen during season.
Violations Of the rules bring unpleasant
penalties. a transgressor who i a
member of the Society may lie expel-
led; be will be reported to any other
society Of which he Is q member, and
the Influence OF the Society viii be
used 10 prevent him from exchanging
or dealing in any way with other ento-
mologlsts. While these regulations may
be difficult TO enforce, il is hoped that
tneif lnnuence ia preserving rare in