The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1908-09-12
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.

Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
The Newest Rotary Engine-An Effective
Rat Killer-A Tell-Everything Watch
Our Power Decentralization Electric
Travellers Tea-Explosions from Ma
chine Belts.
The gas turbine has made such recent progress
that it promises to take its place as one of the
successful motor. Such an apparatus rtquires a
combustion chamber in which the temperature
rises above 5000 f., and from this chamber the
products of the combustion Of liquid hydrocar-
bon fuel are delivered at constant pressure
through carborundum MOBILES to the blades of
the turbine. Besides refractory lining of car
borundum, the chamber has water jacket coil
to keep the gases cool enough for safety to the
turbine blades. The problem of making the
machine itself supply the compressed air needed
to feed the combustion chamber has been tenta-
lively solved, and large turbine that has been
built drives a rotary compressor with an expen-
diture of about 800 horsepower when running
at 1000 revolutions per minute. Some turbines
of 100 horsepower have been actually put to
work, special application having been found in
operating submarine torpedoes. The turbine
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A poison having the popularity Of being fatal
only to the rat tribe has been discovered in the
English seaonion or squill. Testing its efficiency
German investigator ground some sea-onions
with potatoes, and fried the mixture with fat to
crisp cakes. This food surprised him by killing
40 rats in his stable the first night. Remaining
rodents were shy on following nights, but after
three months a second trial destroyed 81, and no
signs of survivors have since been seen.
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The most complicated watch ever made, the
work of Louis Leroy, gives % different indica-
lions. It has two dials. and the mechanism. in
four layers, contains 975 different pices.
Ass
While reliable estimate be made of the
worlds resources in water power, DR.. Rehbok
of the Technical High School Fredericiana in
Karlsruhe, concludes that the supply is more
than sufficient for all needs now evident. The
oreticaly the energy Of the flowing waters on
the earth's surface aggregates 5000 100000
horsepower. or 143 horsepower per square mile
and horsepower per inhabitant. Even taking
the utilizable quantity at one-sixteenth of the
total, estimate regarded as much too low,
there will be 5O0,000,000 horse power, or horse
power per square mile, which is ten times as
much as the equivalent of the 1000 900 tons
of coal consumed in 1907. Though the worlds
supply seems thus assured, some countries have
deficiency and the apparently available 20O0,-
600 to 2.500,000 horsepower in Germany cannot
meet even the present demand. Not even ap-
proximate figures can be given for the United
States, though the following data are supported
by information from the best sources. New
England has developed 100000 horsepower
which may be ultimately increased to 100000
horse power; the Great Lakes region has 1885,
900 present horsepower, with 100000 possible;
the Piedmont region on the Atlantic and South
Atlantic slopes, 1885, 900 present, 100000 posi-
BILE; the Central Northwest, 100000 present,
100000 possible; the Rocky Mountain and Pa
cilc regions, 1,5OOOOO present. 100000 possible.
sts
= The forcing of wheat and other crops by cleo
tricitY has been carried on at Bevington. Eng,
for three years, under the direction of son of
Sir Oliver Lodge. A plot of 19K acres is covered
by network formed of number of lines Of
stout telegraph wire with thin galvanized iron
cross-wires, the whole supported on % large
poles Is feet high and a 2 horsepower oil
engine drives dynamo generating current that
is tranformed to about 100000 VOLTS and is con-
nected by the negative pole to earth and by the
position to the overhead wires. A specimen
from the electrified area and only 25K from
neighboring landau increased yield of 40 per
cent. from the new method.
sss
The sunbeam passing obliquely across our
vision in darkened room reveals dust particles
whose presence in the air would be otherwise
unsupported, and by similar method of cross
illumination Prof. Molisch, of Prague, has made
visible to the naked eye objects and motions
hitherto seen only under apowerful microscope.
Bacteria are thus brought to view. With high
power instrument, DR.. Robert Brown showed
eighty years ago that fine particles suspended
in liquid are forever oscillating this so-called
molecular motion" being especially conspicu-
GUS in the milky sap of the EuphOr6iG the glo-
bules of resin and caoutchouc floating in which
: have maximum diameter of only 10000 inch,
or much smaller than most bacteria. The un-
aided eye usually perceives nothing more
minute than $4,000 inch. When drop of the
sap on glass slide is shifted about in a sun
beam until the proper position is found the
molecular motion suddenly flashes out as rapid
Pickering and dancing of the molecules, and the
effect is particularly brilliant with black back
ground just behind the glass. The visibility is
probably due to enlargement of the retinal
images by refraction.
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Essence of tea is the new product claimed by
an Edinburgh firm. Its preparation is the result
of twenty years of research, as the fixing of the
volatile constituents that give tea its aroma and
cheering qualities has been difficult problem
to solve and had been previously given up. The
brewing of the fragrant beverage now becomes
d matter of dropping teaspoonful of essence
into cupful of water.
az
To show how great may be the generation of
static electricity in German factories, Prof. M.
M. Richter has drawn sparks an inch to an inch
and half long from a 5-inch belt on a wheel
making 10000 revolutions minute. The risk of
explosion in dust or gases seems to have been
overlooked. Coating with bronze or aluminium
powder prevented static charges, while weekly
application of acid-free glycerine was remedy
and added durability to the leather,