The Stark County Democrat. [volume] (Canton, Ohio) 1833-1912, 1900-08-03
SCIENTIFIC
MISCELLANY.
Water -COrrOsiOn of Glass---MO-
tion Of DissOlving Crystals.
THE PROTECTIVE PACKING.
Photographs on Uucoated Metals--The
Great Polar Problem utomatic
Train--s Spinning Machines
OfAnts.

clans, are warned that certain kinds of
glass appear to be so soluble in water
that moisture quickly etches the sur
face and destroys the transparency. Mr..
E. f. Mondy, of Decca college, East
Bengal, reports having noticed the dull
matt appearance of cut wine glass
and of finger bowls in which water had
been allowed to stand, also the spotting
of two decanters which had been dried
after partial draining. These effects
were all due to water etching. This ex-
plains the rapid deterioration of optic
al apparatus in the moist climate of
India, and proof that the fault Is in the
kind of glass used is furnished by the
object glass of 3h inch telescope, the
inner surface of the convex lens being
badly corroded while the adjacent face
Of the concave lens was quite clear.
The motion Of camphor in water is
well known. A German chemist, K.
Schaum, has taken such readily solu-
BILE substances as potassium, cyanide,
potassium nitrate, silver nitrate, calci-
um chloride, potassium permanganate,
and sugar, and has studied their travels
in dissolving by dropping single crys-
tails upon mercury covered by water or
dilute acid. The ACKNOWLEDGEMENTS
in dilute acid than in water-are very
characteristic. The crystal first takes a
zigzag course, then changes to cir
cular path, and finally turns rapidly
on its axis. The rate of motion varies
with the rate of solution and the sur
face tension of the mercury.
The new method of packing used for
shipments of butter from Melbourne TO
Kimberly is recommended for delicate
articles generally. The box is made
from six panes of window glass, closed
at the edges with gummed paper, and
this is given heat insulating covering
of plaster of Paris, the whole being
wrapped in waterproof paper.
The curious fact is oted by French
observer that nightingales devour the
drones Of hive without harming the
workers.
An interesting discovery that has
been forgotten for more thar half a
century was lately brought to notice by
Maj. Gen. j. Waterhouse. In 1912 Moser
found that silver, like its compounds,
is sensitive to light, and that distinct
image could be formed on a clean silver
plate by exposing to sunlight for two or
three hours behind black tablet with
cut-out characters, and then developed
over mercury vapor He obtained SIM
liar results from copper, concluding
that all substances are changed by
light. Taking up the investigation, Gen.
Waterhouse has proven that the pho
tographic image may be visible after
exposure, but that whether visible or
invisible, it is clearly brought out on
metallic silver by mercury vapor or
developing solutions acting on the sill
Yer. The Photographic action on other
metals, except lead, appears to be very
slight, although not fully tested. Ex-
periments thus far made indicate that
the cause of the action cannot be heat,
or pressure, but that the effect is due to
the blue and violet rays of the light.
Whether it Is result of oxidization Is
yet to be learned, apparently pure sill
yer, 1t Is known, often containing acclu-
ded oxygen.
The Importance Of a magnetic survey
in the vicinity Of the magnetic poles
seems to have been overlooked by ex-
plorers. DR.. Cook, Of the Belgian Ant
arctic expedition, points out that q ge-
ographical survey is Of far less conse-
quence, although vastly more difficult,
in the region of the poles. Even the po-
sition of the magnetic pole is yet to be
fixed. Many years ago the northern
magnetic pole was found to be in the
northwestern part of British North
America, but its place Is steadily
changing and is not now exactly
known. Even less has been learned Of
the southern magnetic pole, all that
can be said being that circle 500 miles
across could be drawn on the eastern
end of Wilkes Land with certainty
that the pole is within it.
A novel Russian device for lessening
damage in railway collisions consists of
an iron tube connected with the sys-
TEN OF brakes. Cuts are SO made on
the tube that 1t becomes broken on the
slightest irregularity Of movement of
the train, and this instantly sets the
brakes. In late test at Vershbolovo,
train reaching displaced sleepers and
one passing upon displaced rails were
promptly stopped without damage
Success in waterproofng cloth by the
aid of electricity Is claimed by Mr.. ].
It. Van Gettel, after somewhat dis
couragtng failures. The fabrics are sat-
urated in bath of soluble metallic
salts, to which the dye is added, and an
electric current is passed through them
while In the bath. Suitable apparatus
insures the treatment of both sides
alike as the material is passed through.
The action Is not clearly understood,
but 1t appears that metallic oxide of
some kind Is formed by the nascent OK
ygen liberated by the electric current,
and this fills the pores of the fabric,
giving water-resisting surface, and at
the same time serving as mordant to
fix the dye.
A remarkable exhibition Of the web
spinning powers Of the red ant (Oeophi-
a n ne<|t tt.nA tx.~.