, 1870-01-30
THE CONSTITUTION OF THE sun,

The CONSTITUTION OF THE sun,
Dr.. B. a. Gou1dt Of Cambridge, NasA, Iectured,
IN the evening OF the 2lst ,ns1, before tne Ameri-
an Institute, Of New York, On tTne ConStisu.
on Of the snn-'' After referring to the pyoccsscs
oy which nGtrouonerR have determined the dis.
Lnnee, sze, sad weight Of the centre Of our solar
7ys:er, the lecturer gave an Interesting F<sume Ct
what u known In reference 10 the physical pecu.
a1it'es Of tic solar AalA We make the follow
Ing extracts.
"It Wa once tnonSts that An exterior auer,
dirE the true body of The Fun, VA. tue
source OF his light Ard heat, and tnat within tnt
ahen VIA = Comparatively cold, DARK body, which
ml1ns possibly be ieaaested oy @ neiaqs 60: veIy
be Otherwise, and tnAs the interior OF tho sun
mist be At o temp ratuse snfpasalrH that Of toe
nerce.t nIes which can BE- produced BY human ait,
tne oCe4uon Of hn5taauIy lotes it, significance,
excep:, perhaps, from theological polnt Of view.
"TLe sources ol the light atd neas OF the buu-
the only two Of hts narselloas properties npps.
LEG greatest dln1culty. VIII only eay here that
the most vivid Light developed By huuan art,
sppezrs liIe black spot upon the solar dnE. Tne
highest temperature yet produced BY man il that
evo,yed by trc combustion Of charcoal In o1yceo,
de1. F.; and hN is About nve-eeventbs Of tne
lowest reasonable estiEAte for tho temperature Of
the solar surface. Coa burning II the rate Of ono
~ tAC E1ksAtG 4Oot Ill QoVus GNQ BeEDUQ3
would attain tnis temperature, and Rankinc has
estimated that IN the furnaces Of powerful loco
uouye enaincs poaud Of c3al 10 each square
loot q grave surface u consumed in from ~ 70 ~
tense as lbns at The surface OF tho spn.
"AcUpunX this estimate that 4 hest equal 70
that emitted BY The aun might be attained ny the
combustion OF coal ct this rate Of ope.hsN pound
per second to the sqnzre foot. II Is easy 10 1nd
now long the Whole uass 0! tho sun would last,
were ii Composed Of coal burning 1t that raia'
enH Fof1 ~ nj a n mi n1se.1N AMI
psJ of oxygen 70 fuppmt tie coEouslon. Fer
iorrinT the calculation, We Ind that the e1ttre
Jes1s-tnht i. within period no longer taAa osef
VII ch hnr,sn history e1ttn1s.
'When re view The suu through te.escope OF
Ssss, ~ Of u!th = so,sf eIe -pieee, We see ! bright
olst, In which 20 Measurement fls yet detected
snJ sartafion from perfect circle. THIS circle
IL 4 much more brilliant th1n the psrta near tho
circumference. Mr. il the eoInr brightness equS.
bie IN Other respecte hat the vhOls surface 40
pea Motled n5 sa xarsagns sas r.
nprE the rtnd OF IN oEAaEe, and TO the uneven
surface OF ftnsfpy sea. ....
"Esua!ly, TOO, revttal spois. Q; groups Of spots
sern var!oukly d:s'rinute,f, but ai1osr alFaEs
within a belt crossing tee sun centrally, A7d not
70 w1ce a. one.hal. nis d.ars,eE: These snot1
breadth OF l mio.. which u 1-Ic OF the diameter
of ihe tur. End corresponds 10 seven times that
CT &EE EAfInS 1DQ q bEDEb FEI%U1 u
snd,ces 10 1now that their forms and dimensions
ste urderRotce continual aud rapid cnacges. Or.
dtuat'y, ND, indeed. Always, y ot any coaa:ders-
Tie n;sRnltude, they cont1st Of Two dat.ncs pats,
each Sharply cenaed. VIZ, DARK inner portion
called the uMora or uuc:fns, and A extensive
gtnyisn border. much brighter & than ne nue!e1s,
of.ep, The sun IL seen entitely free from e2oa,
wsNca other tines lheT a1c extremely uuner-
ous. Eore than a,ty naI!ng been seen at one
uu.e. Not unfreqocnty tney arc v11ole to the
cnbed eyc through smoked glass,
Finttsy, 5ct another ar2eatancc presents y
se.s i, the cbse1yLr wtsn telescope Of moderate
rover, viz, patches or srrcaks Of light more brill.
liant tran the rest AID Eot 70 be coniou1ied
with the general nos:llrR Of tne sutfscc, Thea
sIe ca.eu Incu.I, hud arc Rrncrtliy, bat not al-
IN fegtors Dear the :tuu CT margin OF tho SID,
where the tLlnter light, aud toEe other ca1ses,
setd'r them especially consr.c:oue, F1cu'E nay
almost a1EAys 6e +cen n the el9tc v:ciniiy OF T1e
spots. nEd generally to TIC left OF them; h7s tae5
are IOt restricted TO these AtuAt1one, Aua mAy be
toand IN The rE oas where tpota are neTtr seen.
"To eIpaIn the phrnaDeuA OF the Epo.s,
DonenIc Cssstu1 suggested, in 1871. tnat tho Iuo
surface nuat be Az ocean CT ltSht sasrorndlCE 8
tae da,k aud tol:A central body Of The sar, and
eot1c uountaln summit which appears as the
b!ock nucleus Of the epot The suggestive idea
ee % sep of *ses H.
lorRa TO Scotch astronomer, Prot Alex. Wilson,
Of Glstco~, 1co JcAFs lcl. Wilton obsetg I'll hal
ne Ps1Snma!a .. ga;a eSsdsr Mhsn auoSaa, u
equal With on all rides when the spot il near tne
middle CT the tunB dix, alEATb became uAr
roves on the side nearest tae middle Of the SUI,
when lie SPOT approached the c:rcu u1ierence
Hence he ta1esrrd In 10 tha: the spots were iun
refAhaped AFeltufes IN the Luminous envetop.
xh!eh cltcl3sea nc dh,k ooAy Of the sao at tht
oo:1orn, and whose ahIEtcG sides eo7iukoiea tns
peruEbtt.
"1t therefore, the appearances De as sssted By
Wilson, tie Inference eectrS Irresistible that sns
:pcts klc Cr:nL e. IN the glowing envelope OF The
lar. To make aate ot Inc 1tc.a in Inc case, til
DtEecturz OF tho Kew Observatory have carried
out ID cItecuyt examination Of Al the dra EinRl
r51c ayallaoie, and me eourzous prepoadersoc4
Ci oEtc1vAuors In favor Ct this theasy rrust bt
eort:de,ea =. dtrt!telV NJ 'GuE TIE qutsio1 III
De L. Rue s1o speEa ted the use cf 1ne screoscops
10 decide whether me &Fo.s n1c acus!lT cArttlea
CT dcpreaaiols. with ttr eaIe te81lL Bat this II
zrroent, although srrotg o=e, c1n hardly Ut
SSItes. ato thing, arc not Away oaI ,hsy aeen
''bet Nhy sh5nld The sitrltG sides ot such I
cavity AuIett taas dinlnu:en ot the fo!ar las1t
which The penuubtA c1nihh: Because tx
ftlkcr body OF trc san xouI1 be partially sec:
l through II, would be ouf nr9t reply: bat a NO
IeEth iht GsnI Will stos TIA. were tnla the szae
explanation, the peauUnen woGld exhibit dlotf
cnt deS1ccs Of lumroSt!. aod shade gt.dua.iJ
sway 1foE lcll o-!cn,. at liz circumference !:
| peaIarce: bus ths b5ut dsr.es Ct ,ee penumoa
sIc Btarpty dtnled AID III colos s toaesah'y mt
1 ierm thfou7hGps To meet ta.s dif1ea1'I tne
et1eop. q e elSso, rassfe sn sappoed ] sy s ~ &
| ospatre, and strpa,eo oe.weca ,ne trre holy d
the tuu and The atsnosps psc1r. a. the on.er 1lxh'
sso:sspec'e & % f1o nj. ss1i,ce soad acc ,uns III =,
Of lhe spot would b rue ocdi OF TIE snn ~ seen
ts T1estts 5ssz tuH fste: tns . efss: waIsa Mes.e6e
added ihe ltcA ttas tie t.ans2sren. elAsIlc a..
EospntIe IL witch tnc st5.t1m Of clouds mast bs
s s ~ sshs saps5s5 8 es'
tended beyond, the pto:otphe,e- EnArAana
IRON the uue surface CT the suo, thu Etseoal
II,Al ct the surrounding cloudy sassun, and o,
tie ttlnEer peotoepttle- Il u c1Ito1s FAC: thai
! BY potne:ts a11oI ide1ttcal With this taeo.y o
| ctddle Of the fifteenth century. before the cIist
| euce Of tne spot1 WIS kno IN TO as:roaomeEs; Je
! Its nuat be regarded ratoc. ~ fortunate goes
snan IS sseaurs 1neoy. To- nc sTfdenee .!
1.-The general aspect Of solar sposs VA be ~,
| etoEnou1 magnitude o. ecIue fpots has eeen u
| ready meoll3Ied-erEe cnasms which eaEf a
ana cl some two bilious OF square nlles, 80 m
| gcht6 IS large u our csrtn- Their contouA ~
1 rapid changes Ct form and ST., MAKE It recanai
dEIl. e eeuie naoJ tntesrssEs T. qcs5s11s e ~,
| rs molten hare been observed In tntoJ OF Tue =
! eh:cn = ould Imply that theJ arc tnfnns. II
ngss sssnnd iasF esnsTe ia
though il sppe.rs intensely 70 IN coauast Vita Il
sloxlns radiance Of the tu,ro3ndtnc portions, !
i.in issen By 70 mcAss devoid OF bIiShtnes1-
Ias ete Welta.d oJ Wl1uecte that Hc.d y
M Esst q sse Eho:e s,n 70 b. exs,nsnlsnsd. c1cs7
.,ns u. portion EAd;A:tnR tron tac nncleas q
tpoI cur Eyes sonid scarcely he aale . ead1f
toe ot~zaIg bcank Htk5c1el'1 ezula.a h
Gettsaly been co.'s leEcd too lor, yet II wo7;
Eive Inc aIt nuce1s OF q spo: l3I1lous lntcr!
~. rca1:J 9.so0 Times Erea:e1 taAa sa.: Of II
| tp!l n Hoon- 0
"A euross aad frequent a7pe.rnacs Is that
so-cA1 ed Ettcse1, -hich oiten cross Knot uty!t
iuc II lte ptraso-A soCc.ta,ts these Arr L
nuc,ent, II tru IL olter ease, they asr 20 b.ts n
trsn The rtrcmh,n. anc oui1 pcrce7t bic xhca
| conttoai Etth lie uGtl une-eEs Basn ihe1r II