The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-02-20
Correspondence Baltimors County On'o~'
SCIENTIFIC MISCELLANY.
now COASTS HAVE FORMED

In paper on the history OF the deseioPemsa'
ef coasts German geologist, Dr. Fischer, reaches
the conclusion that where coasts hAse 49, ~
nv the erosive action Of waves and stream, eI
rsees ana Eat surface are the prevailing ehasse-
,e-;.tics with semicircular hays 81 small radius
-, servaced coasts and large radius on Dat coasts
Where other features exist they are NANNY ~
tribatable 20 subterransAn movements am se@
parAtivsly recent changes n sne ~ - -.
some modifying effects having Of course eesh
wrought By The sea-
QUALITIES % woops.
Prof. Sargent ands that the strongest ~esa IN
,hs unltea States is the nutmeg hickory 81 me /
A,kansas region, and that the weakest The Ne.s
IndlAn bi.eh. The most elastic = ne ,snss@s,
4 the wood q the Fsews aarsa. The highest
specidc Kravity-upon which Ia general depends
value a. fuels attained By the bluewood OF
Texas.
ExrExr AND VELOCITY OF STORMS.
Pref. Z. LOOMS finds that In the United states
a low pressure area, with only one system OF cy-
elonic winds, frequently has diameter Of l,oOe
miles and that cyclones over the Atlantic ire
quentiy have diameteFs Of 1000 miles. WIDE
spread areas Of low barometer, having several
centres Of cyclonic action, may have diameter
Of 5000 miles or may even form belt extending
nearly, IL not entirely, round the globe, between
the parallels Of 40 and SO degrees north latitude
On the other hand, tropical cyclones are often
only 500 miles, or even less, in diameter In the
United States, the Signal Service records for thir-
teen years show that the average rate OF progress
Of storms for the year is 2S4 miles per nour' rs
ing to the maximum, 2I.2 miles, in February,
and falling TO the minimum, 226 miles, in August.
In Europe storms travel much more slowly, the
mean rate of progress during the five years end
ing 1880 being 1871 miles, reaching the maximum
of 10 miles in October and falling to the miximum
of Ia miles in August.
BIRTH OF THE MICROSCOPE.
MI tba lmDOr-
tant instrument of modern research, is lost IN the
mists of antiquity. rock-crystal lens and a
microscopic engraving were unearthed by Layard
Mt Nineveh, and many of the gems in the British
Museum could not possibly have been cut by their
ancient engravers with unasslsted sight. Later
evidence of the use of water-filed glass globes as
magnifying and burning glasses is furnished by
pliny. Seneca and Plutarch. Alhazen, the Ara
han. made known in Europe the magnifylng
mower of lenses about the eleventh century. 1t is
generally believed that the first microscope with
double glasses was invented by Jansen, in 1880,
although Roger Bacon is credited with previous
invention at Oxford in the thirteenth century.
PROLIFIC WEEDS.
botanist has attempted to estimate the num-
her of seeds found upon single specimens OF some
of the most obnoxious weeds OF this country. FOR
shepherds purse he makes the number 5I,oUO per
plant !; dandeon, II, los; wild pepper grass, 49,
400: wheat thief I, 900; common thistle, 6o,j6o !;
1866 common pursane, 1856, 500; common plan
tain, AZ, 200 burdock, 3S,O6S.
APPARENT DISTANCE OF SUN AND NOON
To determine how far off the moon actually ap-
pears from the eye the late Mons. Plateau De
vised an ingenious experiment, which may be re-
peated by any person. LOOKING s'eaeiy =. tno
full moon a few moments, he turned suddenly
round toward a wall, and noted the size OF the
dark accidental or complementary image when
projected on the wall. When, by moving
forward or backward, this spectral image Is made
TO assume the size of the real moon, 1t must aP
pear to be the same distance from tne observer s
eve: and Mons. Plateau found his distance from
the wall to be about ffty-six yards In similar
manner Mons Stroobant proved the suns apparent
distance to be about fifty-three yards.
MICROSCOPIC WORK AND THE EYES.
An eminent German oculist, DIR. IL. Cohn, has
made extensive researches into the enects OF STUDY
and microscopic labor on the eyes, and he con-
eludes that reading and writing are much more
likely 10 produce short sightedness and otherwise
impair the sight than watch making and other
minute industries.
MISCELLANEOUS
A remarkable variation has been observed IN
the stature of the inhabitants of france. Ii a
line be drawn diagonaIly across the country from
Manche TO Lyons, the people to the northeast OF
the division have an average height of feet
inches while those on the southwest side average
only feet inches.
The first archaeopteryx, the fossil remains of
the Oldest known bird which seems to form the
Connecting link" between birds and reptiles, was
discovered in the photographic slate of Solenhofen
in 1861. Another specimen, recently found In
the same locality, has been sold for S5OOO to the
Berlin Museum.
A ruined city, hitherto entirely unknown, has
been discovered in the province of Adana, Asia
Minor.
A German geographer and statistcian, DR.. A.
Fischer, estimates that annual slaughter OF
10000 elephants is necessary to supply the ivory
exported from Africa.
p-es- Ralksh4ayzen, Of the Leiden Observatory,
finds reason for believing that part of the plano
tary surface of Mars is liquid.