The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1906-08-11
C0rTssp0ndsncs Baltimore County Union.
SCIENTIFIC MISCELLANY.

CorTsspondsncs Baltimore County Union.
SCIENTIFIC MISCELLANY.
Theory Of the Arc-Paper Pipes for Gas
Altitude of Northern Lights-Tne new
MISUNDERSTANDING Of subways--A Hard
Problem-A Beetles ResurrecCon-Ln-
visible Wire-Beach Burning-Tne new
Glass.
The electric arc has been explained by Prof.
]. j. Thompson on the assumption that the posi-
tive and negative electrodes emit electrified
corpuscIes or ions which. under the influence OF
electric repulsion travel across the space OF the
arc and lombard the opposite electrode. Inc
electric current itself is supposed to be con-
veyed By these ions, and their bombardment
produces the high temperature of the electrodes.
In British Royal Society paper. Mr.. A. A. Q.
sWinton describes experiments with magnet
showing that positively and negatively charged
particles actually do cross in the arc, proving,
Is he believes, the absolute correctness OF the
theory.
Gas pipes of paper. as tried in Europe, are re-
ported to have advantages. and are very tight
and cheaper than metal. In making them,
Manila paper is first cut into strips having
width equal to the length of the section. The
strips are dipped into melted asphalt, tightly
wound to the right thickness around core OF
iron rod or pipe, and ceased under pressure
with layer Of sand. The core being then re-
moved, the outside of the pipe is waterproofed.
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The height of the aurora borealis seems to
vary greatly. The spectral light has been seen
touching the earth in Arctic regions, but meas
urements made during a recent aurora near
London show that the red could not have been
much less than 600 miles high, the green being
much nearer the earth's surface.
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Late observation has suggested that the dis
indignation products of radioactive elements
do not always yield helium. and that silver is
formed by the disintegration Of lead.
~
An o1sinoorfne surprise Is the w0rInth or city
subways. It was expected that these. like cell
lars, would be warmer than the outer air in
winter and cooler in summer. but experience
has shown that they are always warmer unless
artincially cooled. This is partly due to the
heat from the respiration Of passengers and
partly to that from the transformation of the
energies brought into use for lighting and for
traction. The air of the tunnels of the Paris
Metropolitan and the New York subway is
found to be about 60 T. warmer in summer than
that outside, and it is estimated that to keep the
variation down to this limit in the New York
the air must be renewed about 200 times every
twenty-four hours. Forced ventilation by fans
seems necessary TO make such tunnels endur-
able in the hottest weather.
@ss
About FIVE fires per week were set in London
last year by petroleum lamps. This gives inn
portance to the problem of producing a cheap
safety lamp, and an association of the leading
English grocers has offered handsome prize
for lamp. costing not more than fifty cents,
that shall be as safe as a common candle under
all conditions Of ignorance or carelessness.
Though this is the fifth time the prize has been
offered, no satisfactory invention has been
found.
A Japanese beetle, of species as yet unde-
termined, lately came into the possession of
Prof. Smythe, Topeka entomologist, in a
singular way. Hearing faint gnawing sound
in Japanese flower stand, the owner bored
into the wood. when he discovered the beetle
larva, which had been there several years.
Since reaching the open air, the warm has de-
veloped wings and grown into fine specimen.
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The present decay of the land is found by Sir
Archibald Geikie to be sufficient, even should
it not be accelerated, to reduce the dry land to
the level of the sea, and threaten another flood,
in comparatively short time.
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Invisible PLATINUM wire Is SbaCeQ 10 nave DceQ
drawn by the late Henry F. Read third of a
century ago. Several yards were made. in
lengths of three feet or less and when wound
upon a white card it could be felt but ordinarily
could not DO seen, although its shadow was
visible. The wire was drawn through as fine
hole as could be conveniently drilled. When
the platinum was reduced to this size, it was
coated with silver and again drawn through the
die. This was repeated as many times as neces-
sary, when the silver was dissolved away. leav-
ing the fine platinum wire. The product was
intended for the cross threads of optical instru-
ments. The animal hairs employed were affec-
ted by dampness, but the brightness of the
metal proved an even more serious disadvantage,
so it never came into use.
.Ts
The "blazing beach, which attracted such at
tention at Kittery Point, Me-, one evening last
September has been investigated by Prof. D. P.
Penhallow. Beneath an inch of sand he has
found a six-inch layer of black organic debris.
including marine plants and fragments of wood
and bones, and the carburetted and phosphuret-
ted hydrogen from this material undoubtedly
ignited spontaneously, as in the well-known
will-o-the-w isp of marsh lands. The flames,
extending 200 feet along the beach and 80 or 40
feet out over the water, rose to height of a
feot, burning three quarters of an hour with a
sharp cracking sound.
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Reinforced glass; produced by rolling two
plates of glass with metallic grating between
them. promises to become of great Importance
as building material In recent French test,
sheet four feet long by IS inches wide and less
than quarter of an inch thick easily supported
1Ol7 pounds, and under heavy weight or exposed
to fire 1t bends and cracks without breaking.
It's strength, resistance to fire and passage of
light admirably fit it for roofs, shop-windows.
partitions and etair-cases.
WHILE CLEANING out an old well on his
farm near Emmitsburg, Frederick county,
Nd, few days ago Lewis Sellers struck a
vein of coal which has every appearance of
being Of excellent quality. A coal vein has
been found on another farm in the same
neighborhood.
FRENCH THRIFT is proverbal, but the China
men who work in foreign countries send home
$4,000 600 year. John beats Poor Richard
in understanding the value of penny saved.
You've Mr.. THAws brigade of lawyers may
not be able 10 save him from paying the PEN
atty of his crime. but they will undoubtedly
relieve him ofthe odium of dying rich.
THE FARMERS of the West are up against their
annual proposition of holding on to their
wheat or accepting cut in price dictated by
the market manipulators.
SECRETARY WILSON announces that the big
packers are complying with the demands of
the Government, thus reversing the old order
of things.
CASTORIA
For Infants and Children.
The Kind You Have Always Bought