The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-06-05
SCIENTIFIC MISCELLANY.
RESTORATION OF SIGHT.


One Of the marvsls promisedat the preaent day,
with good prospect of realization, Is thatths blind
shall see. Already has such partial success attend
ed the substitution of perfect rabbits eyes for i'm
perfect human eyes that the process of eye-graft-
ing seems likely soon to become practical reali-
ty. But there are many eyes which DIR. E. Mar
tin, of Marseilles, has now discovered may be
readily repaired. In very large proportion of
cases blindness proves to be due to opacity of the
cornea, and when this alone is the cause DR.. Mar
tin accomplishes the miracle of restoring sight by
inserting into the eye-ball gold or platinum
tube, through which artificial cornea the rays of
light reach the retina.
ARSENIC AND MALARIA.
Mr.. S. H. Davey, of Cornwall confirms DR..
Tommasi-Crudelli's opinion concerning the effect
of arsenic in preventing cholera and other motto
diseases. Although during the last forty years
many cases of cholera, fever, small pox etc., have
occurred in the country surrounding the extern
sive arsenic works at Bssoe, not single case
has been known within about two miles of the
source of the deadly fumes.
VACCINATION FOR CONSUMPTION.
The chief disease of temperate climates being
consumption, any means which will check its raw
ages must be hailed with joy and gratitude by a
large part Of the human race. In France is now
projected an experimental inquiry into the posi-
bility of finding some method of alternating the
supposed virus of consumption so as to make in
ocuation Herewith practically useful against the
disease, either as preventive measure like vac
cinatien against smallpox, or as means of cure,
like Pasteur's inoculations in hydrophobia. Al
though the chances of success are remote, the in
vestigationis approved by eminent, scientific men,
and considerable sum has been subscribed to-
ward defraying the expenses.
TORNADO POINTS LOCATED.
In q report tothe French Academy of Sciences
on the 172 tornadoes recorded in the United States
in 1884, Mons. Faye considers it established that
there is definite portion of an area of low baron
eter most favorable to tornadoes. The Signal
Service reporters are now endeavoring to deter
mine this dangerous octant" still more accurate
ly. memorable day in the history of tornadoes
was Feb. 10, 1884, when no less than forty five
were recorded in the South Eastern States, at
tended with total loss of 800 lives, $500 injured,
10000 houses and buildings destroyed, and $4,000
people left homeless.
PHOTOGRAPHIC PROGRESS.
The possibility of photographing in the dark
has been shown by Abney, an English expert
menter. He has succeeded in preparing plates
which are sensitive to the rays lying beyond the
red end of the spectrum-the dark heat rays
and with such plates used with a rock salt lens
it should be possible to photograph bodies having
a high temperature, although that temperature
may be far below that necessary to render them
self-luminous.
LIMIT OF HEARING.
It has been found by DR.. TAFT that the ear in
women can perceive higher notes-that is, sounds
with greater number of vibrations per second
than the ear in men,. The highest limit of human
hearing is somewhere between Al 900 and AZ, 900
vibrations per second. Few persons have equal
sensibility to acute sounds in both ears the right
ear usually hearing higher note than the left.
The lowest continuous sounds have about sixteen
vibrations per second.
MISCELLANEOUS. p
The principle of telescopes was described by
Roger Bacon about 1850, and Leonard Digges-
who died about 1573-is said to have arranged
glasses so that he could see very distant objects.
Calico constructed telescopes in 1909, and dis
covered Jupiter's satellites in 1910.
The proportions of the different colors in eyes
among the people of Italy is thus estimated by
Prof. Mantegazza; black eyes, twenty-five per
cent; chestnut sixty -four; blue, eleven and
gray eyes, three per cent.
Prof. L. Weber mentions stroke of lightning
in Germany, which broke window pane and
forced jet of water through the aperture up
ward to the ceiling, part of which it detached
Three bucketsful of water were afterward taken
from the room.
To exterminate the rabbits, which have become
such plague in Australia it is proposed to prop
agate contagious disease among them, and the
experiment is to be first tried on Torrens Island.
The average height of Europe has been estima-
ted by German geographer to be 974 feet.
Switzerland shows the greatest mean height,
1924 feet. and the Netherlands the least, 81 feet.
intermediate are Spain and Portugal, 1928 feet
Austria, .l,6sS; Italy, 1896; France 1922;
British Islands, IA; Germany, 7O1; Russia,
54S; Denmark, lis.
DIR. Burney Yeo, of London, reports the curious
observation that there are persons who usually
drink tea without injury, but in whom when in
depressed mental condition it occasions ndiges-
ton and palpitation of the heart.
Exact measurements of the oscillations of Chin
neys have been made. One near Marseilles,
France-115 feet high and four feet in external
diameter at the top-reached maximum oscilla-
ton of twenty inches during high wind