The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1907-02-16
Correspondence Baltimore County Union
SCIENTIFIC MISCELLANY.

Dust Pictures-A Spring of Glauber's
Stakeholder Bearing for Cars-LQuid
Nitrogen Britain's Thunderstornos-
Earthquake Sickness-Rubber-Fa Faced
Leather-Night and Disease-The Sup
erfuous Stomach.
Acoustic or Chaladni figures, produced in
sand by the vibrations of plate or membrane,
are usually highly symmetrical, but vary greatly
with the shape of the plate. the way it is sup
ported and set vibrating, and with other condi-
tions. In showing the possibilities of this Curl
GUS kind of picture MAILING at late soiree OF
the London Royal Society. Joseph Goold sire wed
q little magnesia on a steel plate several feet
long by three inches wide and 38 inches thick,
supported on four rubber points near the ends,
The symmetry of the figure produced was modi-
fed or destroyed at will by changing the place
Of small clamps. On exciting one of two closely
tuned sets OF vibrations, the other became
active. and quite extraordinary fluctuations
resulted. The modal line extending lengthwise
along the plate opened out into two lines, surg
ing TO and fro. The magnesia in each line per
formed extraordinary gyrations resembling the
the motions of smoke clouds, the two modal
lines across the ends separated into peculiar
spirals, and there we're other strange effects. :.
a ntAcob cdI equipped VIII fOllef bearings,
first adjusted and graphited, has been run in
Hanover without further attention for six
months. The bearings have shown no percepti-
BILE wear, and tests indicate an economy in
power of % per cent. while the actual saving
includes the usual cost of oiIing and attendance.
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The new chemistry Of cold has placed in our
workshops series of liquid substances that
have been known hitherto only in gaseous form.
Investigating nitrogen, H. Erdmann finds that
when passed from cylinder through cooling
worm into cylindrical copper vessel cooled in
liquid air, this gas can be Iiquefied in large
quantities at any pressure between or and rs
atmcspueres. and then, on filtering is perfectly
colorless mobile liquid. Not only ice but alb
solute abolute alcohol sinks in this liquid con-
nrming the estimate placing its density at 0.79l4
Having lower temperature, liquid nitrogen is
more efficient cooling agent than LIQUID air.
1t Is a good solvent for liquids of law boiling
point, and mixes in all proportions, with LIQUID
oxygen or liquid ozone. 1t is inert toward most
substances. and even metals like calcium and
magnesium do not readily combine with it but
mixture of calcium drillings and liquid nitro
gen is ignited by thermite and continues to
burn long time. forming calcium nitride.
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From the records of 20 years, +. J. BrOdie has
found that July is the month of the largest
number of thunderstorms over Great Britain as
whole. For the whole year the largest num-
Der is over the eastern and northern parts of
England. where more than 70 occur. while there
are less than five in the west and south of Ire
land and at most places in the north of Scotland.
The summer distribution is very similar to
that for the year. The winter distribution is
OI1ffQ dfffQrnuf md he 10
bers then occur along the west coast of ireland
and Scotland and the extreme southwest of
England.
Seasickness Is proven. by DR.. Charles Dawson
to be common effect of earthquakes. The
feeling of nausea may be produced by shocks
lasting not more than eight or ten seconds and
whose vibrations have total range of only
small fraction of inch, and in one slight
English earthquake too small to injure any
buildings-about one observer in fifty was
affected. The feeling usually lasts few min
utes. though sometimes persisting an hour or
more.
A solution of the problem of coating leather
with rubber is claimed by Joseph ]. Steinharter
Of Philadelphia. In his newly patented process,
the leather passes under a wire brush that
raises nap on the surface. and is then fed be-
tween two rolls, one at a temperature of 10O0 F.
and the other at SOO', a receptacle filed with
thin unvulcanized rubber being placed above
tSe bite of these rolls, with a funnel shaped
nozzle to convey the material to the face of the
leather and distribute it evenly over the surface.
A third roll. at 3O0o. draws rubber in thin film
from plastic mass beneath, pressing it upon
the already thinly coated leather. The first
adheres. and the layer thus formed is afterward
vulcanized. The vulcanized rubber layer is
practically indetachable, being held by the
fbers of the nap imbedded in it.
Medical treatment almost wholly confined to
the daytime is thought by DR.. Lauder, French
physician, to be serious mistake. Disease is
most active at night-asthma, epilepsy and other
attacks coming then almost entirely-and OBJ
servations have shown that medicine admins
tered in the night hours, or both night and day,
acts better and with greater effect than an
equal dose all given in the daytime. It is ex-
planned that In the nocturnal fasting state the
body absorbs remedies with greater energy,
while they are eliminated less quickly. In
many instances disease has resisted all medical
ton by day, but has yielded to night treatment.
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The entire stomach was first successfully re-
moved by Schlater of Zurich in 1897. B. vassallo,
q surgeon of Argentina, reports having now
performed II pylorectomies, and considers the
gravity of these operations more apparent than
real. Four months after the last complete re-
moval of this organ, the patient was in excellent
health. with no Inconvenience except the ne
cessity Of eating often and but little at time
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In two years French florists change the violet
into two-foot tree, carrying 80 to 300 flowers
throughout the year.