The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-10-30
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
EARTHQUAKE CAUSES.


Prof John Milne, the eminent seismologist of
Japan, concludes that the primary cause of earth
qualxes exists within the earth itself, and that
sl1ch outside causes as the attraction of the sun
and MOON and barometrlc fluctuations, can have
little effect except in causing slight preponder-
ance in the number of earthquakes at particular
seasons. The majority of earthquakes are due
to explosive efforts at volcanic foci. The greater
number of these explosions take place beneath
the sea, and are probably due to the admission of
water through assures to the heated rocks be-
meath. A smaller number of earthquakes origi-
nate at actual volcanoes. Some earthquakes are
produced by the sudden fracture of rocky strata
or the production of faults, which may result
from elevatory pressure. There are also earth
quakes due to collapse of underground excaya-
TONS and these may have been produced by the
removal of matter through volcano eruptlons by
the washing away solution of the earth by
water or by other agencies.
In both the gas jet and the little bulb-enclosed
flaments glowing under the influence of an cleo
trio current, light is produced by the incandes-
cence of intensely heated solids. The carbon
particles of gas are rendered incandescent by the
heat generated by the combustion OF other mole
current compelled to pass through fine carbon
filament heats. the filament to incandescence and
produces light
The great force exerted by growing plants may
be demonstrated by direct measurement. BY an
arrangement of harness and levers President
Clarke, of Amherst Agricu tural College, made
a growing squash register pressure equal TO
thousands of pounds, when finally the harness
many, has lifted more than five inches block OF
stone containing twenty cubic feet
The best examples of the eagre or bore, the
phenomenon in which the tide moves in all at
once, are said to be furnished by the mouths OF
the case of the last mentioned river, in China,
the wave plunges on like an advancing cataract,
four five miles in breadth and thirty feet high,
and thus passes up the stream to a distance or
eighty miles at the rate of twenty-five miles an
hour. The change from ebb to flood tide is al
tide passes up the stream in five or six waves,
following one another in rapid succession, and
each twelve to fifteen feet high.
THE SNOw-LINE.
On the northern slope of the Alps the zone of
perpetual snow reaches down to about 5000 feet
above sea-level, and on the south side to about
$500 feet. In the PyreneeS the snow-ltne is at
height of about $3.50 feet; in the Caucasus, TO-
600 to II 900 feet: on the south side of the Hima-
layas, 12,9sO feet, and on the north 1857 feet;
via Is $40 feet in the western Cordlllera and lo-
900 in the eastern; in Mexico, 1890 feet; in
feet in its middle portion and $500 feet at its
northern extremity; in Kamchatka, $500 feet;
in Alaska, $500 feet.
In an address to the British Society OF Engl-
neers, Mr.. P. f. Nursey lately said: THE facts
1 have brought before you also SO point TO .T the
moral and material progress OF the world Ine
bee that hummed its busy hour through the
bowers of Paradise wrote Sidney Smith, fash.
toned its hexagon with the same mathematlcal
precision which it does now and here. Six thous.
and years have added nothing to the Sagaclty OF
the horse or the intelligence or the dog. But
how widely different with man! He commences
as a fire-worshipper and rises to Newton, Far
aday, Stephenson, a Siemens; He Temps the
river in a few fragments of bark lasned togetner
with thongs of rawhide and crosses the Atlantlc
in an iron steamer of %, 800 tons burden. He bur-
rows in the earth and then builds city with a.
100000 inhabitants. He sticks dried reed in
lump of fat to light his hut and carbonlzes 2OO-
$50 tons of coal per annum to illuminate London.
He takes weeks to send messages on SUCKS 10
MOnteZuma from the coast and at last reports IN
London the details of battle fought IN the SOU
dan the same morning He Stays his foe with
sling and pebble chosen from the brook and
meets the enemy with machine gun firing 6QO
rounds minute by means of its own recoll. He
lays siege to a city with a ballSta, throwing a
fragment of rock, and finally attacks fort with
a gun weighing ITO tons, projecting steel shell
of 1S00 pounds, with charge of 800 pounds or
gunpowder. These are the beginnings and end
ings of science, but they are the endlngS or
science as regards the present only. They are
by no means final, as science never STANDS sui.
They are but the landmarks of our times, winch,
as Emerson puts it, are trivial to the dull; tokens
of noble and majestic agents to the wise; the re-
ceptacle in which the past leaves its history; the
quarry out of which the genius of to-day is build
ing up the future.
The Geological Society of London now has over
3,100 members, and its gardens contain over 2,5O0
living animals.
The island of Chloe, on the southwest coast of
South America has go days of cold rain and sleet
in the year. Yet catarrhS and pulmonary trOu-
bles are said to be very rare among the native
jewellers in this remarkable climate.
Glaciers, the ice-riverS OF lofty mountains,
have been found to move downward from one or
two inches to over fifty day, from ten to twen-
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