The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-01-23
Correspondence Baltimore County O"'o"
SCIENTIFIC MISCELLANY.
INTELLECT VS.. FEcuND1TY.

INTELLECT FECUNDlF1.
A studv of statistical tables has made 1T ap-
rorant that human life is decreasing in quantity
but improving in quality-at least IN somepa
of the world An astonishing falling oil In the
births in France has taken place since the oegin-
ming of the century, the average number OF chill
dren per marriage having been reduced nearly
one fourth. But the average life has increased In
lenpth about one sixth Similar results are oo-
tanned in England, Austria, Prussia, and otner
countries of advanced civilization. Among IN
ferior races births are more numerous anu ilne i
The female of the white ant lays sixty eggs per
minute; queen bee, from 5000 to 5000 eggs
annually. In vertebrates, fecundity diminishes
as we rise from fishes to reptiles, from reptiles to
to birds, from birds to mammals.
A cARBoNIc ACID WILL.
Near Burgbrohl on the Rhine bore-ho about
IT'S feet deep yields large and steady supply of
earbonic acid gas, which is now compressed in
wrought iron vessels and used for various purposes.
It's enormous expansion is emplowed by Messrs.
Krupp at Essen for COMPRISING steel and other
casts, and it is also utilized for mpregnatng beer
and natural water, for fre-extinguishing appara-
tus, as motor force for torpedoes, etc.
ELECTRICITY IN ENGRAVING.
In new engraving machine, Lieut.. B. Carter,
of London, has made an interesting application
of electricity. The machine is chiefly intended
for decorative work upon metals, and rapidly pro-
duces high-fnished results. The words or designs
to be engraved are first furnished, by setting of
ornamentaltypes or stereotypeplate A fine plati-
mum paint traverses this, its motion being res
ponded to by table carrying the metal to be
engraved under the point of the graver. As the
platinum point is raised or let down by the design
an electric current, acting upon an electro magnet,
produces corresponding movement of the graver,
which is thus made to accurately cut in the metal
an enlarged or reduced copy of the types.
EFFECT OF LONG CLIMBS.
During eighteen ascents of lofty mountains
from 5000 to $4,000 feet in height-Mons. Vernet
has made number of physiological observations
on himself. He finds that the strong exertion-
both in mounting and descending-caused Sn
average rise in bodily temperature of about three
degrees; rise in the pulse from about Is to So
in a minute and an increase in respiration from
about 81 to % in a minute.
BEETLE PARASITES OF RATS.
At recent meeting of the Linnean Society OF
of New South Wales was exhibited a curious
beetle-Cryptomma jansoni Matt.-which is
found under the fur of the common rat in Tas-
mania. The belief was expressed that new and
interesting species with similar habits might be
discovered in Australia if the smaller mammals
were examined when freshly killed. Two allied
species from Peru are known, one being found in
the fur and nests of mice.
MISCELLANEOUS
Trouvelot finds some reason for believing that
he has seen second new star in the Andromeda
nebula. With comparatively small telescope
he now observes thirteenth magnitude star which
the large instrument of the Harvard College OBJ
servatory failed to show him in 1874.
The hundredth anniversary of the introduction
of the potato into France is to be celebrated.
In certain Austrian coal-mines work is suspend
ed in dangerous places during a fall of the ba-
rometer, experiments still in progress having
shown that the quantity and intensity of explosive
gases greatly increase as the atmospheric pres
suce diminishes.
the tenacity of copper is greatly increased-even
as much as fifty to one hundred per cent, accord
ing to Mons. Guillemin. The alloys are all red.
Chemically prepared palmetto fiber has success
fully stood remarkable tests as a covering for un-
derground wires.
A remarkable dust shower, which fell in Italy
one night in October, is thought by Father Denza,
of the Observatory of Moncalieri, to have been of
meteoric origin. By others the sand is supposed
to have come from the distant Sahara.
Recent observations, according to Mr.. e. j.
ger expedition obtained few specimens from points
more than 400 fathoms below the surface, and
only single specimen was found at depth of
1000 fathoms.
The production of magnesium having been
cheapened by a new electrolytic process, efforts
are being made in Europe to extend its use as a
source of light. Two prizes-S125 and S5O-have
been offered by a Bremen firm for the best designs
for magnesium lamps with clockwork movement.
The continuous heating of cast iron for several
days in a vacuum, without melting, is found by
Mons. L. Forquignon to cause.-the metal to become
malleable, with uniformly black surface, dotted
with black grains of amorphous graphite.
A new apparatus, called the "meldometer," is
designed for the microscopic study of minerals in
state of fusion.