The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1902-08-30
Correspondence Baltimore County Union.
SCIENTIFIC MIS- CELLANY.

Heat-Expanded Cereals-The Count Of
the Stars--A Target That Signals
Hits-Electrons and Ions-Species-
Making by Temperature-A Scientific
Propeller-A Horse Plague-Vitality OF
Disease Germs-Improved Steam Steer
ing.
The process of expanding starchy seeds and
most starchy substances, by applying heat, as
developed by DR. A. P. Alexander, is not only
most interesting but is likely to have great
commercial value. The granules or particles
are swelled to many times their original size
grain of rice being given eight or more times
its original volume, while retaining its original
form, although with much fracturing. The
available nutrition is much increased. The pro-
ducts are pleasant TO the taste, the process may
be varied to produce a variety of fiavors, and
the material so treated is absolutely sterilized
and may be kept indefinitely.
-.
The Photographic chart of the sky will in
clude all stars down to the fourteenth magni-
tude, the negatives being taken with exposures
of forty minutes and the catalogue plates,
whose stars are to be measured and numbered,
will embrace all magnitudes down to the
eleventh. The Greenwich Observatory, to
which was assigned the region between decli-
nation $40 and the North Pole, has finished its
plates, the measurement and counting being
now in progress. Assuming the star density of
the entire heavens to be the same as that of the
region already covered by the counting, the
complete chart, as made by the eighteen obser-
vatories at work upon it, will contain about 49,
100000 stars, and the combined catalogue more
than 100000.
I'M Co1k
lier, of the French Army, is made up of a series
of metal segments. When projectile strikes
a segment an electric circuit is completed by
one or more spring supported rods at the back,
and the exact spot struck is signalIed upon an
annunciator. The target, instead of being in
disk form, may represent the human figure.
80
AS indicating that risk from lightning may de-
pend much upon soil, an English observer men,
tions having known four or five trees to be
shattered in a neighbours park on ironstone sub
soil while no tree of his own hundreds on stiff
clay was ever struck.
Electricity, in the view of the twentieth CEN
fury physicist, is a material substance. Its
unit, the electron, forms an infinitessimal part
of the atom of any element, and when split Off
it produces a stress In the ether similar to that
due to a negatively electrified body. This sew
ering of the electron from its atom is the gener-
alton of electricity. The remainder of the atom
acts as positively charged body, but it is not
certainly known whether the positive electron
supposed to be about ten times as heavy as
the negative-really exists. Associated with
neutral particles, the electrons become negative
ions and positive ions. Conduction is a wander
ing of these ions. magnetism and the magnetic
field and induced currents are explained by
rapid rotations of the electrons, and the phe-
nomena of the electric arc and vacuum tubes
depend largely upon the splitting up of neutral
molecules, or ionization The radio-activity of
such substances as radium, actinium and polo
MUM is the somewhat forcible projection Of
either negative electrons or positive ions.
-
1t has been long known that the colors Of but
terflies are influenced by temperature. Expert
ments during the last ten years have given DR..
e. Fischer some startling results, and have
shown not only that cold seasons may produce
new butterflies from the old, but that abnormal
heat may yield the same varieties, the changes
being due to retarded development. Extreme
cold, moreover, brings out other variations that
may appear also in extreme heat. He suggests
that these varieties of extreme temperatures
may DcCOmG p0ruldueuJ dC u IuUuTb SJdB6 III LU0
earths evolution, although Standfuss contends
that they never were and never will be anything
but singular freaks.
The latest development of screw propellers is
due to Mr.. c. A. Parsons. The blades are given
reduced pitch toward their tips, small vanes be-
ing also provided on the propeller-cone. and the
effect is to admit of high speed without cavita-
ton and to give greater mean thrust than is
possible with blades of constant or increasing
pitch.
The oxy-acetylene blowpipe of NJ. Fouche,
9q ealtBg @0s q pssef PnEps miES5s ST
in the blowpipe is prevented by moderate
pressure.
Surra, an animal disease of the Philippines, Is
pointed out by DR.. C. w. Stiles as a matter of
great military importance. 1t seems to have
been quite recently introduced from India, and
is due to microscopic parasite. which lives in
the blood and is probably transmitted by biting
flies. 1t is wet-weather disease, reported to
be invariably fatal to horses and mules. 1t
occurs also in camels, elephants, dogs and
cats, and more rarely in ruminants, but is not
yet known in birds. 1t is closely allied to
the tsetse-fy disease of Africa and to dread
The chief symptoms are intermittent or re-
lapsing fever, eruption, enema. emaciation,
ravenous appetite, great thirst, and more or less
paralysis. The introduction of the disease into
new localities is to be guarded against a seri-
Gus calamity.
-.
Microbes live longer in dimly lighted than in
sunny rooms, and Gafky suspects that the les
sened sunshine is one reason why disease germs
flourish better in winter than in summer He
notes thatinfiuenza epidemics have never occur
red in Germany except when the weather has
been long cloudy. He has found that in droplets
such as are expelled in speaking or coughing,
the typhoid bacillus retains its vitality "a hours
in daylight; the diphtheria bacillus, "a to 4S
hours in daylight and days in cellar; the
tubercle bacillus, days in daylight and % days
In cellar; the boil microbe, to 10 days in day
light and IS days in cellar and anthrax spores,
10 weeks in daylight and at least 3 months in a
cellar.
A British engineers new device for steering
twin-screw steamships consists of a special
throttle valve attached to each set of engines,
the valves being connected to tiller by bell
cranks and linkwork. When the tiller is moved
either way from its central position, one throt-
tie valve reduces the steam of its set of engines,
diminishing the speed of it's screw to a degree
varying with that Of the turning of the tiller.
az
Garlic juice, inhaled under certain conditions,
is the remedy with which DR.. W. C. Minchin, of
Kells, Ireland, claims to have cured advanced
tuberculosis.
National Aasooio%ioy, Of altar Narriara