Juniata sentinel. [volume] (Mifflintown, Pa.) 1846-1873, 1866-11-28
WHOLE NUMBER 1929.
CHEMISTRY OF THE ATMOSPHERE.
a divine arranger. must have spread

a divine arrapgers must have spread
out the thin, filmy curtain of the skv,
Ike that thin film of water. the blue
soap bubble, which, like the atmosphere,
reflects and decomposes the light refectes
on its snrlace. rs with light so also the
atmosphere is the conductor Of sound
Professor Cooke says:
every one who has dropped stone
into the water Of still lake has noticed
the system Of waves which, with its ever
increasing circles, spreads in every di.
rectiou from the stone; but all may not
know that when two stones are struck to-
gether IN tie air similar system %
;crial waves spread. in overwhelming
spheres, through the atmosphere, and tha5
it IS the wales breaking on the tympanum
Of our cars, like the waves Of water on a
sand beach, which produce the sensation
which we call sound. Two stones thus
strpch together give rise to waves Of ur.
equal size, following one another at irrag-
u!ar Intervals and such waves produce
an unpleasant sensation CT our auditory
nerves Whi:h We Gull noise But if. in.
stead Of striking together two stones. wt
set in vibration the string Of a piano f5r;5
or the reed CT an organic pipe, We excite
a system OF waves, all Of equal Size. and
succeeding one another With regularity,
and these breaking on the ear produce by
their regular beats what We call a musical
note. If the waves follow one another
with such rapidity that one hundred and
twentyeight break on the tympanum
every second, the note has q fixed fitch
called in music G natural. IF the waves
come faster thau this, the pitch is lower.
What you ale all familiar with as the
pitch Of musical note depends then, on
tho rapidity with which the waves OF
sound strike the ear. and may evidently
be measured By the number o. waves
breaking on the tympanum in a second"
Science demonstrates that the differ
ence between cOlors is Of precisely tie
same kind as the difference between tones.
Eed, yellow, green, blue, violet, Nc, ar5
names we give to sensations caused by
waves of ether breaking at intervals on the
rctina, and color Of corresponds to pitch,
and at every step as th, whole scale Of
colors spreads out before US the analoe7
Of light to sound becomes still more eyi-
dent. And thus wonderful are the forces
the atmosphere holds and the varieties Of
arrangement it displays, it modlae5 ana
d.lfuses heat, Thile t holds aad disper-
ses the mysterious and astonishing agan-
cies Of electricity, just as the electrical
machine is constantly rubbing together
glass and silk; just as We rub stick Of
ealing wax or glass tube with a warm
silk handkerchief, so the air is always
rubbing over tie face of the earth W:ta
greater OF less rapiiity. Nature seems to
be a great electrical machine. As man
guards his roof from the destructive ac-
tion of lightning nS--t'as,itfg 70 The earth,
o.ashing- rending aud burning on its way
by erecting the lightning rod, whose brist-
ling points quietly drain the clouds, or,
falling to do this, receive the charge and
bear it harmless to the earth, so God has
made a harmless conductor in every point
ed leaf, every blade Of grass. 1t is said
that a common blade of grass, pointed
with natures exquisite workmanship, is
three times ag effectual as the finest cam
bric needle, and a single sprig is far
more efficient than the metallic points of
the best constructed rod What, then,
must be the agency of single forest in
lisarming the forces of the storms Of
heir terrors-while the same Almighty.
hand has made rain.dtops and snow-nakcs
o be conductors, bridges for the lightning
II the clouds, alike, it seems, proclaiming
he mercy and majesty of the Almighty
.aad ?-Eclcctjc Eegjcw.