, 1879-01-08
THE ELEMENTS.

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THE IEN ENT1
AAID Dt'1M LIN Los
What BEr. Iockyer 1las discovered. mud the
Deductions lie Draws Thsre{fou.
Bo.son Areyrttftr,
Not long AGO wo referred to the reoortcd t,,s-
,ov.-v ;n.1o hv H. + Nnrn.n aaI,,.s ....
soes'' % ~ ' ~ -,s11 .,.'s .oesse'' t"at
SONS ol tne SUBSTANCES "hfen CHEMISTS hAve
been Accustomed to style "elcmcnls u arc not
elementary but compound Ia their nature,
strce thor, an Tn. 1o,h M r,c,cnoh., ,.., u.
." ..u, ~. w aao 49," ~ er ~. ,as.' ~.
t@oeNyet uas ee'.n'4n.e"lcu " sse noSM eoc'e'5
Tue tesu'ts oi LIE seseasche& Apasmueh ~ ne
may presume that every person who is To-
ssrested in any degree tn science Will be eager
.,,,aaxa-,a. g !. nrrn.r ~, ,ssn.. -. s.s.ss.,
u''e",'e1' 4ope' :" eo''ee' t"e o3'e'na'
report ana explain exactly Ehat hc haa DONE
and what he thinks the rcsult teaches.
We assnrf,a that tho general principles Of
epcctroscohic sccnce arc knowna and particular
y tlis--for discovering and defining which Ar.
spectrum Of an impure or mixed substancs
furnlsftcs the lines belonging tU each of the
simple substances Of which 8 Is made, and that
thcse lities vary In number, itugtl, brightness,
snd thlcknses according to the amount * tho
substance giving those lines. THUS an alloy In
which tho pronortioti Of ono metal greatly cx-
ceeds that of the other wilt give only few OF
The mots ehafacterlstic lines of tho metal Of
which = small amount only "a used. and those
lines Will bo short, naFrow,. and fstut. II the
proportion of tile metal ls. lscreaseu new ttucs
appear, and those Which were before seen be-
come larger and moro disttnrs+ MIR. Lockrcr, 10
his studies uit6 the apectroscopc.. endcavorcd
to eliminate d! tue lines due to Impurities IN
tho su1stance under examination. In this work
u lines 10 tho spcetra Of different metals could
not oo the result o1 mtua! hnpltri;iee, and this
polnt he has dtmonstrateds IT. rttnafncd then
to ascertain! the real causa n tho constant Ap-
r. q the.s II nss s ~. as
that tho spectra OF the hfi9httst7 and therefore
presumably tto hottest, stars. are more siu,pte
than those OK the u'moler. aud .coolcE suns-
Sirius e!iows very eh'ck lpirogcn anu few thin
metallic lines; our sun, which Is cooler, fur
nishcs numerous metallic lines; somc OF the
COOLEST stars add to these tho lines ot some non-
metallic bodlcs; The hyputnesls that In tbs
hottest state oil ondies ara broken up Into their
diminishes compounds iqpsa and, nlorc rcirac-
tory arc made, would flilly cxplau the observed
phcpomcna. ....t
Assuming, howcver, only What Is known, that
heat docs brea's upnnd dissociate souic con-.
pounda, Mr. Lockyor reasotlA tu this way: Sup
pose tllat i, tue substance 4 the Substance d ID
present, either as eonattttlcnt or as mn im-
purity. In the latter caso tho spccttum will re-
veal the 1lhes OF u. in tue :ordcr VI their In.
portanccs and In stzu mud brightness propor-
toned To- tue atuount preAont. Tn tho other
hand, II y is cotnooncnt part Of 4, anj u heat
Will sct y FREQ from It's uqton with othor tub-
seaneea III A, then upon IN !1ncrcasc Of tculpcEa-
turc the characteristic fcatures Of the spectrum
OF a VIII disappear. aud those Of y will become
more trom!hcnt. III other wonls, II A Il 4 aim
plo body. but not quite pure, tta spectrum will
rosnaln constant a. long % the proportion Ut
ltnpurity - UNCHANGED: Il 1t Is compound It's
spectrum Will nut DC constant, but rs the sub
stante is broken up tho Itnca OF It's
compononts Will become more pron,i.
'nent. This principle Mr. LockJer illus
tratea by dealing with tho salts Of cal
eun'. Each uf these salts Inns Its own
deiInlto apcctrunl. As the temperature IL raised
this fades away grudusIly, and tho lines Of. the
,1!esal, calcium !tset, appear III dcilnitc order.
Now. IN examining tho spcctrn Of calcium.
llthum. Iron. and other mc:ats, al diHcreut
tennoeralurcs, chalgcs analogous to tnosc OBJ
arrrctl WHEN heat Ia nrcnktng up known ronl-
pounds, are seen; sud these changrs arc In
s0n,u cnscx even Rrealcr than tl,osu brought
about WHEN known ,u,npouut]S arc under *
untnatlou. Cerlaln strong lines uf cm.ctum are
rnrcly sccn In tho clfolAosphcte, though atwnys
present when the spectrum ID obtained in tic