The Charleston daily news. [volume] (Charleston, S.C.) 1865-1873, 1873-03-05
SPECTRUM ANALYSTS.
What 1t Has Done for Physics, Cho ntts-
try and Astronomy.


By ssspectrumn is not understood In physics
spectre or ghostly apparllion, as the verbal
Interpretation of the word might well lead one
to suppose, but that beautiful Image, brilliant
with all the colors of the rainbow, which is
obtained when the light OF the sun or any
other brilliant object Ia allowed to pass
through triangular piece OF glass-a prism.
The unassisted eye can perceive no dlfer.
ence In the light from the heavenly bodies
and that from various artificial sources, be-
yond a variation 10 color and brilliancy, but
il is quite otherwise when the light Ia Viewed
through prism. There are then formed very
beautiful colored Images or speclrs, the con-
sLlLuLion and appearance or which depend
upon the nature Of the substance emitting lhe
light. The different appearances presented
acterstlc that to every substance, when lumi-
nous in q gaseous form, There corresponds
q peculiar spectrum, which belongs only to
that peculiar substance.
It follows, therefore, that when the spectra
OF diff rent substances have been determined
once for all, by previous researches, and have
been recorded In maps or impressed upon the
tion, 10 recognize at once from the form OF the
spectrum, which body of unknown constltu-
lion presents, the Individual substance OF
which IL Ia composed.
This statement presents In general terms the
nature Of spectrum analysis. II analyzes
bodies into their constituent parts, not as lhe
chemist, with alemoic5 aud retorts, with re-
agents and precipitales, but by means Of the
speclra which these substances give when IN
q state OF intense luminosity.
Spectrum analysis In no way supplants the
methods of chemical analysis hitherto 10 use;
for It's function is neither 10 decompose nor 10
combine bodies, but rather 10 reconnollre an
unknown territory, and 10 stand sentinel ana
to signalizs TO the physicist, the chemist aud
the astronomer the presence OF any SUD-
stance brought beneath It's scrutiny.
With what aculeness, with what delicacy
does spectrum analysis accomplish this task
Wnen the balance, lne microscope, and every
other means OF research at the command
of the physicist and chemist utterly fall, one
look in the spectroscope is SUFFICIENT 10 most
cases to reveal the presence o. substance.
Ifa pound OF common salt be divided lnto
500, 600 equal parts, the weight Of one OF these
porIlons Is called mllligramme. The chemist
is able, by the use OF the most delicate scales
and the application OF special skill, 10 de-
termlne the weight Of such particle; but, 10
doing 30, be comes close upon the limits oil
mis- power of detecting by chemical means tne
presence OF sodium, the CHIEF element Id
common salt. But II that small milligramme
be subdivlded into three million parts, We AT
discerning 1t fails, and yet even this e4ces
sively email quantity is sufficient to be recog-
nIzed With certainty In O spectroscope. we
have but 10 strike together the pages OF al
old dusty book In order to perceive lmme-
dlately IN the specLroscope placed al solne
distance, that the flash OF line of yellow
light which we shall presently learn is an un-
failing sign oil the presence OF soalum
It was 10 be expected that 30 sensitive
means of Investigation, from which no known
slbsI ance ean escape, would very soon lead to
the tracking out and discovery OF new ele-
ments which, I'LL then, had remained un.
known, either because they are scattered
very sparingly 10 nature, or stand out Win 30
little that IL characteristic from some olner
substances, that the Imperfect chemical
methods hitherto In use have not been able to
distinguish them.
This expecla alton was brilliantly realized
even by the first steps taken In this direction;
The two Heidelberg professors, Bunsen and
Kirchof, to whom we are Indebted for tne
discovery of spectral analysis and lts appllca.
tlon to practical science, very soon discovered
with their new Instrument tH0 new metals,
cgsium and rubidium, TO which two olners'
lhallum and lndlum, have been since soasa;
But all the brilliant and astounding results
which spectrum analysis has furnished ID lne
provinces of physics and chemistry nave oeea nt
lar surpassed by its performances id tna' VI
astronomy. 90 dooon,. i.
It is possible by means of prism to decGm ef }ne
pose into it's component parts the llenL VI n the
sun, the planets, the fixed slars, comS.s, nsu
uIm' @ and thus obtain their spectra IN Lhe same
that OF earthly luminous usss4s al bs
s,sra ~ JgiIh The well.knoWn specLra oi terree-
trial trial substances it can be determined, from
their t complete agreement or disagreement,
with q certainty almost amounting 10 matne-
malIcal precision, whether these substances
do or do not exist In those remote heavenly
bodies. The foregoing statements present In
general terms the essence and scope OF
spectrum analysis. Its starting point is the
spectrum OF each Individual substance. and In
order TO obtain this IL is requisite that the sub
| stance should not only be luminous, but should
emit 8 sufficient quantity of light DARK
bodies are not available Tor spectrum analysis,
If they are to be submitted to Its scrutiny tneS
| must frat be brought into state Of viVld Iu'
minoslty.-Ftom Spectrum Analysis LIS
plasned, BY Schsllen.