The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-06-26
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
AN rSrERpRrsrse INSECT.

AN ENTERPRISING INSECT.
"A most remarkable instance of the extension
of the geographical distribution of species is
found by Mr.. j. j. Walker, of the British Navy, in
the beautiful butterfly Anosia plerippus, L., or
Danais archippus, F. Starting from its original
home on the American continent, where it is COM
mon from the Hudson's Bay territory to the eStu-
ary of the Rio de la Plata this butterfly has been
spreading, under our observation, into very re-
mote regions. Crossing 1850 miles of ocean to the
Sandwich Islands, it rapidly and steadily continu-
ed its course over the whole breadth of the Pacific
and far into the Malay Archipelago. Southwark
and westward it has appeared in New Zealand and
Australia. Eastward it has reached the West
Indies, the Azores, and within the last ten years
has even made its advent in the British Isles.
ANTIQUE MARBLES.
A recent interesting discovery is that of the
ancient auarries where the beautiful antique mar
bles were obtained. In the province of Gran,
Algiers, has been opened an extensive deposit
containing gallo antico, breccia and cipone' be-
sides black and white marble. Until this redis-
coyery the beautiful yellow marble, gallo antico,
has been unknown save by fragments found IN
Roman ruins two or three years ago.
SOLAR SUBSTANCE.
Astronomical text books place the suns density
at little more than that of water, but in arecent
lecture Mr.. ]. Norman Lockycr, the English as
tronomer, expressed the opinion that the sun
really has not more than one-eighth the density
of water. If this view be correct, the sun Simply
an enormous globe of glowing gas, possibly liquid
Mt the centre in consequence OF the enormous
measure existing at that part. Solar temperature
is matter at which men can only guess as YET,
and scientific estimates range from 5,OOo TO 49,
100000 degrees.
A French geologist, Mons de Lapparent, lately
called the attention of the Paris Geological Socl-
etv 70 the effect gravitaton has in heaping up sea-
watars about the land. The continents are thus
all situated at the tops of hills of waters and in
crossing the Atlantic the ship has rst to 60 down
hill. then to cross valley, and finally to CHIMP
another hill. The calculation has been made that
in mid ocean the surface may be more tnan nan
n mile Il 900 metres) below the level II would
have if the continents exerted no attraction.
A RARE FIND.
The brick CLAW deposits of Hainstadt, Germany,
have been found by DR.. Strohecker to pc slngu-
larly rich in several metals hitherto very scarce
Particularly cerium, glucinum, lanthanum, dldy
MUM and Yttrium. The first two OF these seem 70
the worlds supply.
PAsTEUR's METHOD.
Ifa section of the spinal cord of rabid dog be
inserted into the brain of a rabbit by trepnlnlng
the latter animal becomes mad IN ABOUT niteen
days; and when the virus from TINS raooiI Is
transmitted to a second, and from the second 70
a third. and so on by the same method OF lnocu-
Iation. the rabies soon becomes more and more
pronounced, and the developing or incubation
neriod becomes shorter and shorter, until at the
end of fifty NEGOTIATIONS most severe form Oh
madness results in about seven days The virus
from the last rabbits is of great purity and OF IN
variable strength, so that similar sections OF
sn;nal cord NAV therefore be relied upon to pro-
duce exactly similar effects. 1t has been turther
shown that the virulence of the pieces OF cord
slowly and quite regularly disappear when Kept
in dry air. and remains unaltered when preserved
in carbonic acid gas. An understanding OF these
makes it possible to have constantly on nanu
hydrophobic poison varying IN strength from
harmless mildness to deadliest virulence. IL Is
upon these graduated poisons that Pasteur de-
ponds for his remarkable method of protecting the
animal system from hydrophobia. Experiment
ing first with dogs, little meat broth containing
weak virus was injected under the skin the 1rst
day, and was followed daily by injections OF IN
creasing virulence-that is, preparations from
cord of shorter exposure to air-untii IN rev
DAYS the fresh or strongest virus was used. Wnen
it was demonstrated that without injury the AMI
mails had become entirely refractory to rabies
from bites-even when inflicted before treatment
or NEGOTIATIONS of any degree. The method was
first tried on a human subject in July, 1885, when
immunity was conferred within ten days on a boy
considered to be in great danger. Since than sew
eral hundred bitten persons have been treated,
and thus far the only failure to prevent hydro
phobia has been in single case where the In
EQUATIONS we're attempted too late.
MISCELLANEOUS.
A glass of greatly improved quality has been
made by Dr. Carl Zeiss, of jena, for microscope
detectives. Lenses of the new glass give images
of wonderful clearness, and have greater resoiV-
ing power than has hitherto been known.
By new German process finely divided tin is
precpitated upon textile fabrics, giving flexible
and brilliant coating.
young German chemist has kept blood I'M
coagulated for many days by coating the interior
of its receptacle with oil :,
Leaves of larch which had been rolled into balls
the largest more than foot in diameter-by
the whirling motion of water have just been ex-
hibited before the Berne Naturalists' Society,"
Such balls, free from cementing mud, are formed
in certain Swiss lakes, and in other places are
produced from various plants.
The Dammar bee (Trigona lauiceps) of Burinah
makes a nest in hollow trees from rosin collected
in the forests.