Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1871-07-20
Scientific.

impairing its medical qualities.
JULrUs hRAFFUB, a Prussian enpi-
neer, has invented a machine when
viii manufacture ice without chemicals
merely by the compression and expul.
sion of air. The specimen machine.
now at New York, can turn ont two
tons of ice a day, and the capacity can
be increased to twenty-five tons or more
A MUSHROOM will.lift a paviAg-stone
many times its own weight, rather than
turn over and grow sideways, which If
would appear so much easier for it To
do. So tree-roots will throw over i'm
mensely strong walls, against which
they have grown, though one would
think the pressure against the softer
soil would give room for their develop
ment.
An exchange says that it knows of a
boy who accidentally swallowed a silver
half-dollar. They gave HIM warm wa
ter and tartar emetlc, and antimonial
wine, aud poked their fingers down his
throat until the boy thought he would
throw up his toe-nails After while
doctor came along who understood
such cases. He administered small
dose of patent medicine, and in less
than ten minutes the boy threw up the
half-dollar in five cent pieces. Science
is a greatt hing.
TOBACCO grown in a cold climate is
stronger than that grown in mild one,
and a similar statement is true with re-
gard to celery. SO it appears from an
Ill, f,AA l.A = l1,.
ceutical Society, where ii is maintained
that in the less vigorous vegetation of
cold climates, as compared with that of
warm regions, the active principles of
plants are moe concentrated in the
leaves.
An ingenious author asserts that the
length of a mans life may be estimated
by the number of pulsations he has the
strength to perform. Thus, allowing
20 for the common age of man, and
sixty pulses III a minute for the COM
mon measure of pulses in a temperate
person, the number of pulses in his
whole life would amount to II, 207, 52O,-
600; but if, by intemperance, he forces
his blood into a more rapid motion,
so as to give seventy five pulses a min
ute, the same number of pulses would
be completed in AS years; consequently,
his life would be reduced fourteen
years.
A MACHINE has recently been perfect
ed in London, with which writer, US
ing a pen in the usual manner, can at
the same time produce a duplicate so
small as to be invisible to the naked eye,
yet 50 distinct that microscope will
reveal every line and dot. Almost useful
application of the apparatus will be for
prevention of forgery, as private marks
can be made, on notes and securities,
legible under microscopic power, but
which no lmltator could see or even
suspect the presence of.
PROF. ABEL, chemist TO the British
War Department, has, after prosecut-
ing numerous experiments, succeeded
in perfecting the new explosive agent
recently produced by him under the
name of picric powder as a material
for charging shells. Although it is not
so violent in action as gun-eotten,
nitro-glycerine, or picrate of potash,
picric powder is a much more powerful
explosive than gunpowder, and has
other qualities, which appear to render
it peculiarly adapted for employment
in shells. Its merits are that it may be
readily and eXpeditiously prepared,
and that it is remarkable for It's safety
as compared With all other explosive
agents, being somewhst less sensitive
to ignition by percussion than gun
powder. The President of the Commit
tee of Explosives at Woolwich, having
pronounced the new powder worthy of
further experiment, it viii be tried I'M
der various conditions in order to ascer-
tam its suitability to the requirements
of the service.
DIR. f. C. CALVERT describes, in a
paper read before the Manchester Lite
rary and Philosophical Society, a series
of experiments tor the purpose of as
certaining the conditions under which
iron is most rapidly oxidized. One of
the important points arrived at is that
carbonic acid promotes oxidation OF
iron, He also substantiated the curious
fact, first announced by Berzelius, and
now well known to soap and alkal
manufacturers, that caustic alkalles
prevent the oxidation of iron. Calverts
researches prove that the carbonates
and bicarbonntes of the alkahes pos
sess the same property as their hydrates;
and that if an iron blade is half I'M
mersed III a solution of these carbon
ates, they exert such preservatiye IN
tluence ON that portion which is ex-
posed to common air, that it does not
oxidize even after aperiod of two years.
Similar results were obtained with sea
water, to which carbouates of potash
add soda had been added