The Middlebury register. [volume] (Middlebury, Vt.) 1850-1882, 1874-03-03
soiui-specirum and Spectrum inaiy.

Were the light Of the sun composed "
only one kind of light, as it seems to be.
all objects 10 the world would be of one.
aud the same color. The rays themselves
have no color. But the different rays
which we call red, orange, aud so forth.
excite the sensation of these different col.
ors. This subject Of colo', is one Of great
interest. but is outside Of our preseut
traiu Of thought.
A parallel may he found 10 sound
While air in motion its 1T is not sound.
yet under proper conditions.sir 10 motion
.xcitos all the varied sensations Of SOUND
ever heard.
Tue solar spectrum is ray Of sunlight
divided Into Its primal colors, consisting
Of the colors Of the rainbow. Tne usual
method Of obtaining this spectrum is TO
let the sunlight into room -therwise
dsrk) through very narrow sli. iu \
window shutter which then passes through
4 triangular glass prism by which it is
bent aud divided into red d,orange, yellow.
green, indigo, blue aud violet. which are
seen on wall or scr, en- ut n proper dis
lance. the cuIcrs always appear in rue.
session, ia the order named the .ed he
" bent least aud the violet ruost ffou q
light line. Ii slI the rays are sg,iu com
lined, they produce the common white
light Why this is so, no one is able to
explsin Some OF these colored rays
combined with their complementary col.
'rs-aS blue and orange, indigo aud yell
low-will also produce white light. These
lpon being redecomposed, show only their
original constituents. Besides the rays
which We see, there are the heating aud
The chemical rays. Though each Of these
extends over largo part Of the visible
pectrum, the heating rsr is most active
in aud near the red rav. while the ohemi.
al ray is most intense in the vicinity Of
he yellow. While all these rays. heat.
ug, lighting, and chemical, are essential
70 vegetatiou,t is believed that the vslue
f the chemical ray has. by ui,scientific
,eople, been little understood and there.
ore under.estims'ed. Ia terminating
..cd-, generally hid from the visible ray q.
ney are only acted upon by those unseen
,y-; aud in the photographic art. the
hen,loa i, the mnst important Of all.
E,ch color OF the spectrum always on.
'upies the same relative position to the
'thers and in Of the same relative siEs.
Each ,i-ihle ray ls a color By itself. and
sll they are seven primary rolors a,
,as been proved by the attempt to de.
'ompole and still further divide them
nd thus has been dIsproved the theory
nat some Of th in'ermrdiate colors we've
'rmed by the overlapping or bIeudiug o
so contiguous ones.
Besides these colored sections of the
pcctruu, there are 6ne. dark lines run.
ing vertically through them. Though
Newton experimental much 10 the de.
composition Of light, and with solar spec.
rum, he failed to discover these dark
ines, for the resson that he admitted the
ght through round oridce, thus obtain.
ny series Of spectra. overlapping each
.rher while later scientists admit the light
hrough narrow slit, aud thus obtain u
ure spectrum.
Though the existence of dark lines was
irst noted by DR.. Wollastou. II Ger.
uan opticisn. Fraunhoter 6rst accuratel, i,
mapped aud counted SIG. Since. other
cleurists, by division and subdivisions
through succession Of pri-ms have been
,be to record aud count thrnugh he Wis:
BILE spectrum. more than 5000 Of these
dark lines. which are still called Fraun.
hofers.
The map accurately representing the
solar spectrum, appears like Il rainbow.
iued ribbon, the colors crossing it, and
through the ribbon. crossing it Iikewi-e,
are numerous minute dark In ~ aud clus.
'ers Of lines duer than the fines, spide,
Web.
These lires in the spectrum. slway.
,old their relative positions. aud are Iaud
"ark- in spectrum analysis TIE sub
lect Of spectrum analyst, |, a comparative.
y new ou'', and 10 based upon tho princi.
,io that every elementary substance
/ brought into glowing gaseous state,
:mts light peculiar to itself.
Philosophers are able. by various
methods. to obtain the luminous gases OF
! these elements. and when tho light from
p any one Of them is passed through a per.
feet optical instrument called spectre.
scope, and spectrum is obtained. the
coioring and marking Of this spectrum
! indicate a particular substance. That il
% say, that each elementary substance,
Is sodiam. iron, hydrogen. sine, aud NC
nrth, has each its particular spectrum.
anlike that of every other one. These
.peetra are made up of different coors
l'f-ring in brightness and in breadth,
'nd generally separated by moro or Lore
pace. The spectrs Of the most common
dement's have been mapped and xrr
amiliar to scientist, 10 this department
+ knowledge, Spectrum analysis il u
cost licate aud searching method b.,
,hch to obtaiu q knowledge OF the pres.
moe of all simple elements and BY il
several substances in nature. unknown
before, have recently been discovered.
Investi CATION has revealed the fact tn at
the bright lines iu several Of these spec
'ra, CORRESPOND. or are coincident with
he dark Fraunhofer's lines 10 the solar
pectrum, That is, that their position
nd comparative sixs are the srme iu
10th.
A Kirchoff. the great astron ,mer and
scientist was experimenting in the spsctrs
,f the metals. using Frauuhofer's lines as a
, Kind of guide or boundary for his work
no was struck with the remarkable coin.
cidence or counterpart, they we're to the
bright lines he was finding in the metals,
, aud 10 this way first dawned upon the
mind Of man the idea that they we're pro-
'luced by the existence of these elements
in that luminary.
Moonlight, aud light from the planet
f Venus, which two bodies are thought "a