The Mankato free press. [volume] (Mankato, Blue Earth County, Minn.) 1879-1924, 1882-01-20
G. NJ. HOOPER.
Scientific Gossip.

Interrupt communication between the
several corps Of the French army, owing
to the adoption by the latter Of per-
fected system Of flashing telegraphy.
Great Britain employsin underground
occupations no fewer than 378, ISL per-
sons, and the length of the galleries
where the mining IS carried on Is found
to be 1914 miles. The greatest depth
of the coal mines Is $500 feet below the
level of the sea.
A skeleton of a kangaroo was found
at depth of twenty-eight feet by the
Kilcunda (Victoria) coal prospecting
party. Professor Macoy believes that
the skeleton belonged to an extinct
genus, and indicates that the deposit in
which 1t was found is of the piocene
age.
NJ. Duprez has contrived register
which gives excellent results In making
rapid measurements with the interven-
ton of a single Bunsen cell. He has
already succeeded In reducing the time
of q double signal to about one-sixteen-
hundredths of second. It L. not neces-
sary to have the circuit closed longer
than one-forty-thousandths of a second
in order to give the signals.
Sir John Lubbock maintains In his
last Linnean Society paper that bees
prefer blue flowers to those of any other
color. But the objection may fairly be
raised, How, if bees have 80 much to do
with the origin Of flowers, have we 80
few blue ones? He met this by suggest
ing that all flowers were originally green,
and then passed through white or yell
low and generally red before becoming
blue. He says that"an ant may live
seven or eight years.
Les Mondes reports that Major Lauer.
an Austrian engineer, has made some
experiments at Krems, on the Danube,
which have excited great attention. He
placed a cylinder loaded with dynamite
upon the surface of the rock and explod-
ed it by an electric current. However
small the quantity above the cylinder
the rock was 80 crushed that it was east
ly swept away by the tide. tits estima-
ted that the adoption of this method
will reduce the cost Of removing sub
merged rocks 40 per cent.
Professor Sylvanus Thompson, in lee
turing on the storage of electricity, stat
ed that the two great advances that
science had of late made were that the
Gramme machine was reversible and
the other that voltaic battery is revcr-
sible. The latter was the counterpart
and complement of the former, while one
had solved the problem of the electric
transmission of power, the latter solved
the problem of the electrical storage of
energy, but such storage must not be
mistaken for the storage of electricity
itself.
In endeavoring to drill glass and porce-
lain, or to cut them after q stated de-
sign, there are many difficulties which
lead to failure. A French firm adopts
this plan: Disks of soft metal of from
to 9.8 inches In diameter are covered
with diamond dust. These disks are
then mounted on arbors which revolve
at high rate Of speed. Glass or por.
celain can be cut by disks in few sec
onds after any design. Cylinders con.
structed on the same principle drill holes
in hard substances very quickly. The
instruments do great deal of work
without showing any deterioration,
From the phenomena presented by
refraction, DIR. A. Kerber has estimated
the height Of our atmosphere to be be-
tween 117.4 and 1877 miles. The ed.
itor of the Journal, of the Franklin In.
stitute, says: "Some Of the observations
on meteors and auroras have led the
conclusion that the atmosphere reaches
q height of more than 500 miles. La.
places limit of synchronous rotation
would allow a possible height of more
than 5000 miles. The theory Of Fresnel
and Grove that the luminiferous ether lie
only very tenuous atmosphere, would
make the portion which belongs to the
earth of the same height as Laplace's
limit.
Bismarck says that the next genera,
ton will care more for pie than glory
And there'sagood deal more in pie than
glory.