Edgefield advertiser. [volume] (Edgefield, S.C.) 1836-current, 1845-12-31
COW NMUNICATIOs. e.
For the Adoertiser.
ARTICLE Ill.
LIGHT AND OPTICS.

LlGH ANU VI 1lNS'
J;ob, Is one OF the three imponderabies, end
one Of the filty-seven elements which compose
our globe. Such great affinity has light t"r
hest and electricity, that when either o, 'ne
two latter are disengaged, hight Is also d'Seh'
gused. ,u.,, H.. 0f.., or
certain agent rs heat is the effect oi tne ope :.
ra,;on of ,Re matter Calorc. The elect "i
light being mistaken fort the caus''' Is imagine
nar,lv from this circumstance, that the theory
nrl;yLt il not better understood. tits very ev-
dent that vision is no, the agent which prodn'
ces the faculty Of seeing bu, is the result OF she
nc,ion of material agent, oil the EXPANSION oi
the optic nerve-the Ieiima. from thence trans
mi,,el 10 the sensorium commune, and there by
thc molecular action of the brain. the sense
of vision is produced The mnst superficial
PbvsioIosist, is convinced tiut the tacnlty oi
oIfScion and taste is not the agents or ma'erI-
ale which prodIce these different SENSATIONS
but are the effect Of the application oi odofler-
ons or sayory particles upon The snydrriau
membrane Of the nose, or mucous membrane
of the mouth. from thence conducted 10 Inc
brain, and there by a mysterious operation OF
this organ, the sense oi sthcll or TASTE, las III
v;sion' : is produced Th" idea that vision is
,he result of the molecular action OF lhe bralii
c,n also be supported from Tue observance ~
certain pathological conditions ol llie animal
economy. Taste and smell are so corsidera-
hIv yi,ated in ceruin Affections that many sub
Stances which were quite agreeable, have an
entirely different odur.. aud lungs when III
health were sweet hec"me III disease hiliei'
and vice versa. So in vlsinn--ohJecis whirh
,could not be seen ia health can be seen III dis
easc, ( (Mania n; ;por,u.) That vision Is made
,ey.dent,t to the mind, by the molecular or some
other mysterious operation o' 'he orath' aho
is the effect and not the canse Of bshl, is,
ehink, very conclusive.
Having shewn that vision IS the effect of
come occouIi agent, aud not the ca,lse oflght,
sh,n Druseet to exp,se lle different theories !;
a accoi,n, Tor the ,plienomeua of light. 1t Is
well knowmIhat there are Two npai theories
nxtant To explain the different phenomena OF
lisht. These theories are called the undnla'
INV or Huyshenian, and Newionan or Cor
pnscnla.
"Ol,he rndnlat6ry or fiEyshcTan theory
Grs, That All Excessively rare sublll and elastic
medium or ether ills all space, and pervales
nll material bodies occupying The intervals be
tween their molecules: mud either by passing
freely among them, "r 10y lis extreme rdrliy
offering no resistance To the motion ot the
annreciable by the must delicate Astronomical
observations. and having inertia. but not gray
i,y. Secondly, that the molecules nt the cher,
are succeptible Of being sci IN motion ny the
ari,ation Of the PARTICLES OF ponderable mailer,
and tha, whit u any one Is ihns Sci IN nohon IL
communicates Il similar motion 70 those alJa'
cent 10 it, and thus the motion is prnpasaied
farther auG farther. in all directions, acc"fdlng
m the same mechanical laws, which regulate
the propagation IN other eaSlic media, as ar,
water or solids, according 10 their respective
constitutions. Thirdly, that when regular Vi
bra,ory motions of a proper klud. are propa-
eated through the ether, and passing through
our eyes, reach aud agilate our retina, they
produce in US the sensation Of light, IN man.
ner bearing more or less close analogy to
that in which the vibrations OF the air affect
onr auditory senses with that of sound. Fourth,
that as in The doctrine of soand, the frequency
of Inc aeriul pulses, or the number ui excer-
,;o,s 10 and fro, from the point OF rest, made
bv each molecule of the air. determines the
Mitch or note, so in the theory OF light, the
frequency ofthe pulses. or number OF impul
.es made oL onr nerves in Il given lime ny The
e,herial molecules, next IN c.rutact with them.
determines the color ofIght, aud that as the
absolute extent OF the motion 10 and fro oi the
nar,icles oftht air. determines the t0ndReSS Of
the sound, SO the amplitude, Or extent fthe
excursions of the elherial molecules, from their
narts of rest determines the brightness or IN
tensi,y ofthe light" Sir John Herschels Prin-
ciples of the undulaory theory
or the coIpuscnlar, or Newtonlan theory.
nFrst, that light consis,s Of particles oI matter,
nossessed with inertia. a.d endowed with nt.
trac,ye forces, and projected or emitted from
alllumiuous bodies. with nearly the same velo'
city, abou, 10000 miles per second. Second
that these particles impigning upon the rellna'
stimulate and excite vision; the partcles whose
inertia is greatest, producing the sensation of
red, those Of The least inertia Of violet, and
those in which it is intermediate. the interme
dialc colors."-Sir John Herscheps principles of
The Corpnscuiar or Nc,ctonian theory.
From the circumstance that The Newtonian,
or Corpuscular theory. cannot satisfactorily
account for I'LL the phenomena of light
Philosophers have yerecentIvtmaniiested an incI.
nation TO abandon the theory of Newton, and
return to the undnlalory theory which ac.
counts for light. by the vibrations or undull.
lions of an ETHEREAL fluid, which .pervades all
the universe, aud penetrates all bodies, occupy.
ing in them the inteysices between their mole
cples, and even penetrating the primitive mole
c,,fc iisrIr