The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1903-12-05
Correspondence Baltimore County Union.
SCIENTIFIC MIS- CELLANY.

Electric steel Making-A Simple Hy-
grometer--Moving a River-Wood
Lighter Than Cork-Thorns-Action OF
Soap-Smoke Gas.
About fifty species of fishes are known to
have electrical organs, although these organs
have been carefully studied In only five or six
species. Electrical fishes occur in both salt and
fresh water, and the best known are various
species Of the torpedo in the Mediterranean and
Adriatic Seas, the gymnotus Of the Orinoco in
South America, the malapterurus or thunderer
fish of the Nile, and various sea skates found
around Great Britain. Prof. McKendrick, who
has been making special study of these fishes,
finds that the electrical organs are of two kinds
modified muscles IN the torpedo, gymnotus
and skate, and modified secreting glands in
the thunderer fish. Both types are formed of a
vast number of microscopiical elements, each
with nerve fibre from nerve centre having
large special cells. But the organs themselves,
and not the nerve centres, generate the cleo
tricity, and they are specialized for the eco
nomical production far beyond anything reach
ed by man.
For measuring feeble Examinations, like the
zodiacal Light and Gegenschein, NJ. Touchet
has devised special instrument, resembling a
theodolite in appearance. 1t is provided with
constant fame and slit regulated in width by
a screw with divided head, and when the fllu-
mination of the field through the slit exactly
equals the light to be measured, a reading is OBJ
tanned that is easily reduced to standard.
80
new German process yields metallic calcium
chloride. The furnace has carbon walls as
anode and small rod of iron through an insu-
lated bottom as cathode. the temperature being
Iast hofr k1.o ofk
spongy mass separates on the anode, and on
compression with tongs or otherwise becomes a
solid containing nearly ninety per cent. of cal
cium.
An interesting chapter in lunar history in the
opinion of Maurice Loewy, may be traced upon
set of beautiful chart photographs lately pre-
sented to the Paris Academy of Sciences. The
pictures show, for example, that the craters
were not on the borders of seas and oceans. as
on the earth, but were distributed In all parts
of the moons continents-a fact indicating
greater volcanic activity on the lunar surface
than on the earth. Tycho's singular white
streaks, radiating outward $50 miles, are attribu-
ted to lava or cinder flows from the crater. NJ.
Loewy believes that they give positive proof of
former atmosphere, and that their termina-
ton on the borders of the lunar seas may be ex-
planned by the extinguishing action of water
sss
The smelling of steel by electricity is still an
attractive problem. The two furnaces built in
1900 reached technical solution by producing
steel of fine quality, but the furnaces were
ruined by fire before commercial success had
been attained. Another furnace planned by
the same makers is to hold 1870 pounds with a
yearly capacity Of 1900 TONS and is to receive
the current of 800 horsepower dynamo
Though microscopicaliy identical with crucible
steel, the electric product is claimed to excel in
strength. density, uniformity, toughness, and
ease Of working when cold.
-
For simple paper hygrometer 1t is recon-
mended that white bIotting paper be saturated
with solution of ounce of cobalt chloride.
ounce of sodium chloride, rs grains of calcium
chloride and ounce of acacia in 8 ounces of
water. The following changes of color give
rough indications of the atmospheric moisture:
Rose red, rain pale red, very moist; blush red,
moist; lavender blue, nearly dry; blue, dry.
-
The changing of rivers channel is the great
est project now being considered by Italian en-
gineers. The Sale flows into the Mediterranean
near Salerno. but it is to be tapped in the hills.
and the water taken across to the Adriatic
-
remarkable tree of the Mmosa family,
called Marea by the natives, was lately men
uoned by Capt. Truffert as having been observ-
ed IN the Tchad and the Bahrel- Ghazal regions
1ggrows twelve to fifteen feet high with trunk
about ten inches in diameter. 1t is found only
In damp places, and, while it is much lighter
than cork 1t is firm and strong in texture. A
piece of wood about six feet long is carried nv
native soldiers In time of war; This is slight
burden, and it serves not only as a shield in bat
tie but as bridge or raft in crossing streams.
40
Inc spines or thorns of plants are largely a re-
suit OF insufficient nutrition. This may arise,
states Ferdinand Faideau, from impoverished
SOIL, dryness of the atmosphere, or intensity of
light, and removal of the unfavorable conditions
tends to reduce the number of the thorns. Gull
tivation lessons the thorns, and in many cases
causes them to disappear altogether after a few
generations. Experiment and observation have
proven that humidity tends to diminish the
number or cause their total disappearance, and
like results follow reduction of the light
"a
The cleansing power of soap is thought by H.
W. Hillyer to be largely or entirely explained
by the power which it has of emulsifying oily
substances; of melting and penetrating oily
textures and of lubricating texture and i'm
purities so that they may be removed easily.
He believes these properties may be explained
by the low cohesion of the soap solutions and
their strong attraction, adhesion or afinities to
oily matter, which together cause the low sur
face-tension between soap solution and OIL
80
A novel Belgian method of dealing with smoke
consists in driving it by fans into porous re-
ceptacle over which flows stream of petroleum.
The smoke is caught and turned into gas that
gives great heat, and can be used for running
gas engines.