The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1903-08-22
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.

Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
Writing at a Distance-Dust Stars-A
Disease of avements-Imitation Noun
tain Building-In the Sea-Serpents
Home-Armed Crabs-Improved X-Ray
Vision-How Lightning Makes its Path
Malaria of Horses.
The telechirograph, or writing telephone, of
Ernst Karl Gruhn, is ingenious if not simple
The transmitter is pencil whose lead has lit
tie play in the metallic casing, and the pressure
of writing closes vertical motion current in
the up and down strokes and horizontal one
in the forward movement. These currents con-
troll magnets in the back of small mirror in
the receiver. This mirror is rocked by the mag
nets, and pencil of light from concentrating
lens is reflected upon strip of sensitized paper.
The DETECTED ray of light follows the move
ment of the writer's hand, producing facsimile
of the pencils marking exact enough to serve
as a signature to check. The sensitive film is
drawn through developing bath by little
electric motor.
That dust should settle in regular figures
crystallizing so to speak, like the snowflake
seems rather surprising. Using plates heated
10' or 15o above the atmosphere, Mr. w. ]. Rus
sell finds that the settling dust always tends to
produce regular geometric forms, which are
always star-like but are made by the shape of
the plate to vary from three-rayed to eight
rayed stars. In each instance the rays are of
uniform length and form perfect pattern
while superimposed stars often produce very
beautiful figures which appear under micro
scope
fungus that rapidly destroys wood pave
ments is giving trouble in English cities using
such paving. The fungus spreads from infected
blocks to sound ones, and the only means of
checking it seems to be careful inspection of all
wood before laying and the prompt removal of
infected blocks
Electric sparks are always obtained from kites
reaching height of quarter of mile, and in
crease as the kites go higher.
s+s
In laboratory experiments on the formation
of mountain chains pressure has been applied
in one direction only. but in the new apparatus
of Lord Avebury four beams of wood are drawn
together by screws so as to give compression in
two directions at right angles to each other.
The space between the beams is two feet square
and nine inches deep. In this space are placed
pieces of baize separated by sand, and the work.
ing of the screws pushes the SAND up until it is
lattened against the plate-glass covering the
apparatus, when casts are made of the different
layers of baize The results are found to imi-
tate closely much of the folding and other phe-
nomena observed in Natures mountain build
ing The ridges in the bottom layer, as in ma
ture are narrow, short precipitous and greatly
broken up, but become wider, longer and less
steep until the layer below the sand on the top is
plateau like. Many variations in natural condi-
tlons.can be represented.
-
In spite of the efforts to trap the animals of
the deep sea-: many forms-perhaps some of
great size-mustss still be unknown. The Prince
of Monaco, one of the greatest marine natural
lists, has shown that life of some kind probably
reaches the deepest ocean bottom, and in a very
ingenious way he has proven the existence of an
octopus that appears to frequent the middle
depths of the Atlantic. Noticing that the dying
sperm-whalo elects some of its latest food he
fastened to secure some of this. 1t included
fragments of such an octopus, and one of the
antennae, though incomplete measured not less
than 20 feet in length.
The curious habit of carrying live sea-ane-
none in each of its two claws is ascribed to the
Melia, genus of small crabs of the Maldive
Archipelago. NJ. Borradaile states that the
crabs claws are too frail for use in defense, and
1t is not clear whether the anemones are held as
means of protection or as a trap for food.
80
A pains taking survey of the fishes of the Nile,
extended far up both Blue and White Niles, has
just been completed 1t adds II new species to
about 90 known before, and gives much other
valuable information.
A"s
The x-ray stereoscope of NJ. T. Guilloz uses a
ffIb "a 60 cd hot Io
oscillated between two positions. The oscila-
lions are given by cam making 800 revolutions
per minute, and so arranged that only tenth of
one position of rest to the other. Two distinct
photographic images are thus formed with dis
placement varying with the degree of the tubes
oscillation and its distance from the screen.
Two shutters, electrically controlled by the os-
cillating apparatus, allow the right eye to view
one image and the left the other, vision being
entirely cut Off during the change of the tubes
position. The combination of these images gives
an apparently solid reproduction of the object,
and the effect is claimed to be superior to that
obtained with two tubes or with tube having
two anti-cathodes.
-
Some time ago B. Walter showed that an cleo
trio spark feels its way from the positive pole
to the negative in a rapid succession of prelimi-
nary sparks OF increasing length. By some ex-
cellent photographs with moving camera, he
has now proven that lightning similarly estab-
fishes a conducting path through the air by a
series of minor flashes, and that as a rule the
lightning passes from the cloud to the earth as
a series of continuous discharges.
~
The horse-sickness of Cape Colony resembles
human malaria, and attacks animals exposed in
low-lying swamps or left out at night. Horses
pass safely through affected districts during the
day. The Government bacteriologist of Natal
suggests that mosquitoes carry the infection, and
has shown that horses protected by wire gauze
or smoke may remain unframed in the midst of
the disease while the unprotected succumb.
~
Earthquakes are due to discharges of cleo
tricity between strata of good conducting and
insulating strata like granite and silica, in the
view of Prof. Piudski. The discharges gene
rate gases, to which the observed facts are
mainly due.