, 1879-01-10
NATURE OF THE ELEMENTS.

Bio 1kGV3lnflttna OF Lne H1teCtftut.
MIR fnrk TtMts.
At q recent mcctinc Of the Royal Society IN
London, AIr. j. herman Lockyer, F. Il. g., read
lunr paper. In whiel. he discussed the evlcntc
derived from sEcctrosopIc observation Of the sun
and stnrs, and from laboratory experiments
which has led him to the conclusion TINT the 60
called elemcntA Of the chemist arc Ia reality
compound bottles. In order TINT tho line Of nr-
eumcnt followed by Atr. Lockycr may Lc un-
dcrstoos,. 1t will be necessary briefly to refer to
the rce,tts Of previous researches. Al a rule,
In observing spcetra, tue substance TO bo
examined Ia volatilizcd In gas
hane, or by meana of spnfks from. an
nugie9 IT, eo and ts Gt Is aTs to tall o.
then gcneratlv ono In which the lines run across
the entire field, but, by tntcrposlng a lens l,e-
twccu tie spark apparatus aud The s!it OF the
spectrascone, Mr.. Lockycr was enn1lcti to study
the vartous rrgons Of the heated vapor. aral
thus to establish the fact, already noted bv
sonle previous observers, but 10 WHICH little nt-
tentioia bad been paid. that atl the lines IN tho
spectrum Of tue substance volatatIzcd IT'D not
extend to equal distances from tn. poles. lie
then slowed BY tho aid of this incthol TINT III
the case Of alloys containing different prunor-
present fa very small! quantity, its spectrum Was
reduced 10 fts sisnptcht fofn'. tho line Gr lies
lonccst In tho spectrum Of tho pure hnb-
stante alone appearing, hut Tint. On increasing
kn9 AHlHUk u kNlb SOl!hLtLuEHES 4tS NlnEE lluEA
gradually appeared 10 ths order Of their lengths
In the spectrum OF the pure substance. Similar
nDyervatl Ions were nadu with compound botlirs.
1t wa+ also noticed TINT the ii,ics furnished t,y
and uun,brr, but also in brightness and thick
mrs., at1Dr6tng to the felattYo amount prcacHt.
Armed with these facts, nnd With the object
Of ultimately asrertalnIng tnnre definitely thnn
nlcnts IRA present in tbs sun, Mr.. Lockycr,
| about fur years nQo, commenced ths
preparation :ot a map ef q particular g.
q o Sf tae stsc g, fs tse
aan,c region Of thG solar spectrum. For this
purpose about. 1,0o0 photographic of spec.sa
of Ill the yarsous metallic elch,cnts favo been
taken. antl, in addition, morn ttun t00, ,0Gl eye
observations hays been made. Az It Is almost
impossible to obtaiu puse substances, ilp p!,o-
togtapls llayo, been carefully cotnt,anu III ortirf
to eliminate the lines duo to impurities; the
inG regarded na proved II lta lopgcst and strong
rst Iino was ahgcnt fron' the photograph OF tie
element un4rr examination. Tie result Of a1i
TIC hypothesis that identical lines Il, different
speetra are due 10 ttnpurEties IL not sufficient,
for he ttua sl,aFt.lne rotncitlences between the
anrctra oil many Inctals IN w,l1cI! the freedom
by the ahrcnsc Of tho lonRcst lines. tic then
a.ls thnt five ycara ngo he pointed out Tim:
there afs many farts aud rnaty TRIMS of thought
suggested BY eo1sr ond .tclInr physics whicl.
nS' tea. t,,s e'em:"s o:"ss .hs~stses hs-e' or, j;
vii evcllte, sonlu of them. arc compound bodies.
Thus It would Appear that the aottur u stGr tho
hInre PH, ole 10 It's spectrum; Tor tile brightest,
an1, probably tho hottest, stars, ns SIRIUS, tlr-
rirh Apcctra showing Hrly very thick hydrogen
lines null fcw yery thin metallic lines, ctlarat-
terstic OF elements OF low atomic weight: wl.tIa
the eboer stars, Rugli rs our sun, ore shown uv
their gpeetEa to contain u inurlt larger Huinber
Ut metallic elements than Stars such - Sirius,
bnt TO not.Iaetaic clctncnts; md tho eos,lest
stars furnlss! tuted hand Epccttn characteristic
ut compounds vi metallic with noil-u,etuillo
cEcmchts und of non.nletat!lc elements. These
tarta uppcArto nlrct with simple OK xnIsnntton II
II Do supposed TINT as !!,e temperature inerrases
tho cnnpoun'!s aro tl1:t o,o!:sn up Into thsr
'nente tl'cn UNDERGO, dIssocIstlon Of do
composition iuio !" "c,etnrnts" uf lower
atou,tc wcight. pr. ).oekycr ncxt considers
phenomena, suppo>!nE that 4 contains Il ~ an
tnrnrlty uad as constituent. III both caBes Il
will have a spectrum Of its owu. II. however,
Il prcsrnt as an impnshY, will merely atl III
have ntove explained, whereas, II Ii constituent
oI A, It will add It's lIucs oltG to the extent
to Which ts dero;1lpt,sea aud u "a SIT at librs'
IT, 80 that as .hc. temperature increa,cs the
spectrum Ut Il viii fade II Il hr cunluuuIAi
baiy, whereas 1t Will mt Jude II A be trl. rlr.
.ncIt. Moreover, II 4 h1 u roMpou,t! .boly,
the lunGcst lines IT. one temperature wttt nut Is
the lnus~st at another The paper cl,lr!ly deals
with discussion, IRON this point Of view, ol
thu spcrtra Of calcium, .rou, hyalrogeH, aud
li,h.um ~ observed ut yaEi.nls temperatures
aud It Il shnwn that precisely tic kin'laf rhanc1
which " tu br expected 0n tle Aypot thcxiR Ut the
.nt,rcmcntary character Ut the c!r1tcnt llas beer
fuunu tu take place. Thus, rael Ut ll:o sa!ta a
calcium. 40 long uh the temperature Is hc!0w u
csstain point, bas t!cln!te spectrum" ii Its owh
but IN thu Temperature IL raised tile spectrum u
Thu alt gradually utes out anti very thu llcs
s!uu to the metal appear in the blue nnd v!olr,
poTttuna VI tiu spectrum. AZ tbs temperature
TIM 4,
intensity, tho vsolct II aud lines, u they nrt
eatcd, hcing sill thin; IN thu sun thu II aud n
ll,rs are very thick, and the line III the blue Il
Q. less intensity thnh cttl'Ss, mud 's'ueh thtnne
cent star photographs show tt'ut both the II ant
X ltues are present til the spectrum of Aqua.
tic latter being, ilnwescr, only ubont half til.
breadth Of tic nrnlrr; but that IN tho spectrum
ot Lysu and Sirius, only the II l!nt Of calcium
! | Is present. Similar cydeneu tnat taese differ
: cnt lines may represent different substance
; uppcats 70. .be aitul!led BY !'r"t Young
having seen the line injected inso tL,
eIIroInospi.rc suyenty-dyetlcs, tho X line fit,
, tiu.ea: but the blue line, which Is the all.lni
was only injected thrice. lu ,tc spcr.rum o
irou. two sets ol three lines oeur In Tho tegiot
between II und q. which arc highly character
istie Vi tlls metal. On comparing plutogTaah
> tween pol"s vi iron lle relative internally q
tl.csv tri,iets IL seen u be absolutely reversed
tho itnss barely visible in the spark photograph
bcioy among tho most prominent in that Ut lh
= solar spectrum, while tue tr1plct, Which /
, prominent .tu .Ie spatk photograph. /
Represented by liues not halt 50 tLtek iu th
= aolar spectrum. Prof. Young has olscsyc'
during kolur storms Two verY fatnt lines .
1nu iron spectrum ncar U INJECTED thirty time
into lhe chFoMosphcro, wA!lc one VI tlu lines Q
tae tnplcs was only lujectcl twice. aheso facts
str. Lorkycs cuuteuda, ut 0sce III :se With sl.n
q rIe cxp!anaton IL IL b. admitted tAat the l,ne
= are produced by tho vibration u several utstuc
e n,uIccuics.
II The !nhtua. spectrum exhibits scries Q
;. changes with rtae IT temperature ptccixcl
:. uEplagous to those observed in tue vRsv of cal
8 | eiuIEI.
}. Iu discussing tho hydrogen spectrum, Nj
< | IoSkyer a1dnces q number ut most inIpustal
. aud inieIesttng f4cts and speeu!atlons. 1t