None
384. 355; IncldenUl ocoomuca. 385 388 ; In aoobJ. aUrv 259-262 Coauata, ndnkkad by oorcwal raja, XS7 ; rariaUaw of ooaaiploouuaaaaBi with tha aoUr rnodjlton, 158 Common, pbotagrapli of a globular olaatcr, 438; rariabilit} of aoeo- poncota, IS I ; pbotofraph of a comr Ury orUala, 446; a trtpla group of bebuba, 454 Comla, lUaaory firaeaat, 1 Copaland, b»lium liita la apavtrnm of Orion oabula, 1 74, 499; uoltmra or atara, 356, 357 ; -i-^tmm of U OriooLa. SSOi of U Ganuiiomm, 109; apactroacoplo dartactlon Of babolw. 4sO. 442 Coma, talluric abaorpUoo. 33 ; ■poclral aariaa, 63 C«n»a, problam pr«aaa«a4 by, 9, 140; taaaity, 16 ; partadlcal aariatbms 30, 137 - 139 ; atnwtura, 133 - 137 ; chro Doapbark relatlona, 139 ; ipactrum, 130, 131 ; pelanaauoa, 132; photo* Craphy. 132 136. 141 ; dark loarkiaga la, 184 ; roUtloa, 136, 141 J taaoriaa rt-gaMmp. 187-140 Corobtatn. lai|Kirtabca of la aolar pbriaca. 53 ; aabUny. 90 ; probata* qaaUiiva. 61 ; ■paotnim, 180 ; noD<abaorpUra, 140 ; an unknown vlamrut 111, 188 Cortla, atructarv of aua apota, "6, 77. 90 1 tb-lt aJUfnatlona la activity. 98: ataraga dnralion, 86 ; thatr apaatra. 90. 91 | rotaUon of faenba, 146 ; apactral aaoiuallaa ot Not* 1'onwi. 393 556 PROBLEMS IN ASTROPHYSICS Crab nebula, discovery, 617 ; spectrum, iia Crookea, Sir William, rucla-elements, 33, 84 Crneia, £. a typical oiygen star, 190, in Cygni, /}, colours ud spectra, 214, 265 Cygni, Xt bright-lino spectrum, 226, 227 ; colour -changes, 355 Cygni, V, nature of spectrum, 186, 233, 234, 235 ; irregular variability, 106 Cyan'.us. first notice of Orion nrbnls. 496 Park stars, problem they present, 176, 177, 180 ; probable origin, 276, 277 ; coupled with bright stsrs, 289, 292, 293, 298, 317. 400, 401. 403: two classes, 403 ; galactic relation*. 649 Darquler, dltcovary of annular nebula, 484 D* Arrest, drawing of a nebula, 443 ; observations of nebuloua atari, 464, 461, 465 ; sharpness, of 65 Andro- meda?, 466 ; stellar satellites to nebubc, 433 ; annular nebula, 403 ; nondescript nebula, 620 J variable nebula*. 623, 626. 626 Davidson, black marking! In prominences, 110 Dawes, black openings in sun-spots, 76 ; colour of & Cygui, 261 De la Ran, stereoscopic view of a sun- spot, 61 Dcnibowski, colours of doable stars, 260. 261 Deneb (a Cygni), spectral relationships, 193, 197 Denning, observations of a vsrisble nebula, 628 DenUndres, pliotography of prominences, 9, 19, 96, 103; selective photography Of the nun, 49, 99 ; facular flame*, 100 ; electrical origin of chronio- spherie luminosity, 116; ultra-violet prominence spectrum, 119; the son as a bright-line star, 121 : coronal ■pec trofi rani*. 132; ei>|rcrimenU on coronal rotation, 186, 137 ; coronal heat, 141 ; spectrum of Altsir, 281, 284 Dewar, researches at low temperatures, 60 Dissociation, In nun-spot*, 90, 96, 163 ; of us lei tun, 114 Doherck, colour of Hind's star, 267 ; of > Delphi til. 260 Doppler's principle, 4. 19, 106, 297, 890 Double stars, evolution, 176 ; variable tints, 269 262 ; spectra, 263 - 270, 276, 276; indistinguishable from apaotroacoptr binaries, 297 Draco planetary, helical 474 , spectrum, 475 Draper Catalogue, 173 Draper, Henry, illusory lines in solar spectrum. Draper, J. W., illusory dark lines in solar spectrum, 28 Dreycr, observation of a double nasi 464; non -nebulosity of 55 Aw mods*, 4S6; alleged illeplai asnssM Omega nebula, 612 ; obssveaalaTaw variable nebulas, 523 Dumb-bell nebula, analogous way* 481, 61T ; structure, 616; assess* 617 Dun6r, spectroscopic measure* of sun's rotation, 19, 144. 146. 144. 1 283 ; spectra of son-spots, 64), I spectra of fourth- type stars, 316, 3 219, 220; colours of Oft Harts 260; revolutions of V Cygao, 1 312 ; minima of Z Hercuhe. 314 Danlop. a blue cluster, 411 Dyson and Lewis, clones, twio of Caaw -•jr. East, refraction m sun-spots, 80 Eberhsrd, spectrum of x Q7f»l SSt Ebert, temperature of the saw, I theory of the corona, 139), 140 Eclipse*, solar, obaer*at>c*M rfsirsssg, 19, 20 ; disclosure by of iwewrnn* la] 44 • 46 ; of prominence*. 100, 11 of coronal halo, 123. 125-128, la* ! Eclipse*, stellar, 299-301. KclipMug stars, mean densely, 371; I 307, 310, 318, 814 ; rotaliaaal saw 282, 283 ; enumerated aad osss-Hn 299. 318; light ■ curves, 303. 31 spectra, 316 ; absent froeu rfsassi 438 Eddie, light-change of I CsrpsW, 331 Eisig, spectrum of oxygea. 33 Electricity, spectral tnliietseaa ssay factly understood, 6 : nadalatevy , 1 supposed affrolirsDeaa att spheric UlumiaaUoa, 116; in corona, 187-140 F.lkin, parallax of CapeOU. 31 measuremsnta of Um PWaa4aa, 418 EDerman, spectrographs of carnesa ski 186, 216 ; of a Wolf Rayet atac. 31 Kills, solar and Disgust* ■ irisaal 164 Kngelmann. colour of I Cysjai, 331 K»pin, spectrum of a Herraha elujsjai 183; catalogue of fourth type; at 216 ; spectrum of e> Fetus* 330 ; R Coronas, 347 ; colours of star*, 1 266, 257 ; light-cluaga sf R Cy, 867 ; suswatted s*r*o4 of 63 Cy INIiKX r»57 389 ; rvl tUn In Parana* clnavrr, 412 Sv#mhMl, photoprmpUi of Huh apartnim, 40 : cooamuUon of mrraUur Uyarr, 47, 48 ; light from •pot-umbn, 76 , tbalrapactra,93; proniioruc* -apartrum, 113. 116,119; titanium in thw «' aphar*. lift Fabridui, Tariabllrty of Mtra, 346. 349 Ficulax, connection with aputa, 74. 101, 161, 166, 161 ; rtttna tad dlatrlbn- tton, 08. 100 ; pkotoffApUd, 99, 100; rotates, H5 M7 Faya, i tin eufi - rotation, 149 Fanat, map of atari Id al 11. 410 Wiijii dk«turb«mc of nrrfniDK atratain, 60 ; depth of chromoapber*. 102 ; obaarvatioaa of prooitueacea. 103-lOf. 116 Fhilay, paraHai of a-it-iraa. 213 ; niagni- toda of w Carina. 371 FiWtfrraM, elactrioal relation* of U*c •oUro.rona, 140 Flanimarton, colour* of double atar*. 260. :''■. I Flamalaad, nnbuloail*- of SO Aodromada*. 466, 467 Flaoery, variationa of R Scull, 369, 364 KWtninc. Un., dlaoovma* and claaaifton-- tlon of <mriahU aUra, 186, 277 ; it»**ctton of an aclipalng alar, 816; duplicity of a l.yrw, 338 ; aarlabillty of W Piippie, 362; of V Dalpfclni, 366 ; dUcu*«ry of Nu*a Norma*, 382 ; -.1 Nv» Cnuuri, 384; of Ko*a Hagmaru. SVf- ; of a planetary nebula, 47rt : •p.-ririim of a atar la Libra, 612 KoDulbaut, character of •ptctrum. 201. 30a Fowli-i, phoWgrapli- of ImUaai aclipa*, 180 Frank*, colour* of .tar*. 267, 280 KraanJlofer. mrvaj of tbo aolar ipwlnia. 21, a Kmubolaf ■ Htm, their HiUrptrtatk-n, 18, 17, », 96, 2t\ Si; motion dia plapafiiaaU, 19. 48, 141 ; uuld en tilled r. -.nhmiii. 86 ; variability, 87 ; eflret* of pr»«ur* no. 38, £1 ; structural DoapluiUa* 40, 41. 43. 343; ban- •yutll ity of ot Urinating MraU, 60, 164 ; . '.'3, 146 ; in fatal*. 98, llfl. it> pftflartMl (-omnal light, 182; lH •)«*■! nun i>f Afidroiuedai nebula, 440 Fravt) !»<•! of ma >|«iu, 79; Daanttl l-j*»r«r of aajbraa, |]| 12 ; r*frwt»oa tn the »un, 167 (iadohn, diaeotery of jttna, 33 'lale, diacorcry of an annular naUla. 439 (JalUum, recognition tn the tun, 28. 11*.; 1l a CyjiiL 1V3 Gal toil, dcacriptluu of anlar corona, 128 UauUer, atiu-*pot nod aaanglfj period*, 8 Uaaaiboriiiit, K. rarboo Uude bnght to tpeednjin, 246 fianilnoriim, U, diffuse aapect, 361 ; light rhangajt, 886. 366 Caatnlnoriim, f. a typical abort -poriod rnriable, 819, 328 ; ort.lt, 829, 890 ; mean ben of iu dam, 831 336 (-ill. Mr laaei.t. Cap* CHirobniDttaraaK. ITS] »pi«-trneTapli nfo,' VoLaorl. 182, 269 ; oiygnn In aUni. 191 | a* CCn- tami a replica of tbo aun, 192, 199 ; paralla* of ftrtiu, IBS ; of Pcanalhaul, 202 | of Cnnopua, 204 ; apaetrtNB at « CariHSf, 236 ; pbolograpb of Arjo nabula, 607, 508 Ottam rtxlnw of a Carina. 871 tfoodrfcka, tanaVallty of ^ Lyrae. 337 Oore, dlwovary of I' Ortonia, 360 lioiaant \.n$\xi Horn In > Caaalnpaaaa, 248, 249 ; apaelral ebaafaa tofiijrm, 348 ; altra-vloUl apactrna caf Noam Aoritaa, 181 ; of patmtary na4fana. 479, 482; of anoalw In Lyra, 488 ; «f<tnmb bail aabqla, 617 ; pboiofrana of naclaar atar to Lyra eabula. 487 (ioald. r*d atari. 26*. 281 ; rarlaaMMty of rW oaifliuni. 306 ; of R Trianftilt 324 ; of ly PupiiU, 362 Unrity, titidUc-rim mat ins; action, 2 ; mnl- t«r*«lity, 3 ; maint«>naoc«of aun'abcat by, 14 ; nautraliaatlon of affaota npoa aolar apparnlaraa. 1 6. 6 1 . 60 ; cflarliva- ocat In Ptara, 194, 201. 206, 207 ; gala of power with oondaoaatioa, 27t ; Is* 6n*Dor on aUlIar tanparaluraa, 274 Oroonabrl<lg», mapDitud* at R Caphaa, 869 Oroacb. corona of 1867. 127 Oroaar, otaaatnrataana of vanabW a&ara, 284,361 Gmaa and Laakt* apactrnni of K laaoaar, 227 (lathnlok, long roaqaallty of Mkra, 848 liagaa, minimum of V Gaainania, 344 | periodicity of 8 Parati, 370 flaha, naclaar atar ta Lyra aaaalar nabula, 488 lla'a. photography af rmmioariraa, 0, IB. 98, 110 ; dupU.lt) of D„ 57 ; carbon in tba climinc-jibFT", 116; apectra of imMolnanom 118, 119, 121 ; pro nrnatfoa fnrna la dayllgbt and daring •olipaam, 190; magnatir ralatlnaa af chromoapaaix 167 ; aprvti 558 I'KOBLEM- ASTROPHYSICS carbon lUra, 177. 185, 210, 220; bright lines In. 185. 217-210, 288. ■peclrum of Nova Persei, 392 Hall, measurement of stars la Prsssepc, 412 ; invisibility of star in I.yr* nebula, iH Halley, aurora of 1719, 156 ; magnitude of 0 Eridaui, 373 Halm, function of the tun'* smoke - envelope, 72 ; effect* of solar periodi- city upon terrestrial movements, 158 ; theory of temporary start, 398 Hansky, dark marking* on prominences 111 ; dzawiugi of coronal types, 128 ; coronal structure, 130, 140 Hartley, spectral eerie*, 53 ; gallium a chromospherie constituent, 118 Hartley and furnace, detection of gallium Hues in solar spectrum. 28 Hart wig, mininia of Z Herculla, 314 , tight -change of S1 Cygni, 367 Hurxer, solar rotation, 148 Hantelberg, Investigations of metal he spectra, 20 ; vanadium in the ran, 32 Hastings, constitution of solar atmo- sphere, 71 Helium, a constituent of prominence*, 19, 113, 119; non- absorptive in the nn, 29, 60, SO. 93 : terrestrial dis- cowry. 29, 50, 174; spectrum, 57, 58, 113. 114 i properties, 59 ; absorp- tion in sun-spots, 94, 195; a con- stituent of gaseous ceboUa, 174, 477, 478, 480, 499 ; aoaorption in *tan, 174, 181, 190, 191. 195. 225, 228; emission In star*. 176. 186, 187, 226- 228, 850 ; in Nova Aurigse, 878 ; in Nora Persei, 398 ; miied bright and dark aerie*, 229, 230, 238, 239 ; in 0 Lyra*, 338 ; yellow aeries represented in nebula-. 530. 537 Helium stars, distinguished by Vogel, 174, 181 ; characteristic* and varieties, 189-195; nebular relationships, 189, 190, 372, 277. 279, 482 ; distribution, 196, 54S ; pass into Sirian start, 107, 272, 277 ; with bright lines. 229-238, 248, 251 ; mean dcniitv, 272 llel inert, catalogue of star* in M 11,410 ; their variability, 411 Halmholtx, gravitational hypothesis of solar suttentation. 1 4 riertchel, Alexander, spectral series, 53 Uertchel, Caroline, discoveries of nebula*, 441 Hartrhel, Sir John, nebulosity ronnd « Ononis, 190 ; cnlonrs of stars, 258, 239,412 ; observations orolnsten. 414, 425; nebulosity of 15 afonocerotis, 420 ; globular clusters catalogued, 428; observation* of nebol*&,« 41, 443, 440, 447, 450. 458 | daub** isJatl 452, 453 ; nebulous start. 403, U4 405, 400 | Owl uobaU. eernti*. 233 ; colour* of doable a****, 269, 200 ; oheerTstsan* of Mum, 341, 849; nebulous stars. 400, 443, 443; planetarv nebulas, 471, 481 ; ssa*aaa nebulae, 484, 489, 498 - sssssct «i Trind nebula, 509 ; maJtftnla saar m. 609, 511 ; variable t&ebalat nlii — ■ *al by. 620, 523 ; dark note n Stssraa*, 541 HeTelins, magnitude of R Cepaet, Hind, red atar, 258; Cancri, 306 ; of D detection of T Taun, 371, 523 ; temporary nebula. 623 Huffier, parallax of stars in Ursa. 290 Holden, polar rays of toe dark lane* in Herrul** cj helical nebula, 474 ; annular nebula-, 485, 490 ; Saturn nebula, 492 ; *s*jl in Orion nebula, 603 ; varsabtirry *f • star within its eotspaat, 504 . — ■ - of alteration in Omega a*fcal*. 613. duplicate nondescript aebaUa, 519 Homstein, the son's rotation, 144 Howlett, conformation of 31 Huggins, Sir William, speetroBTaphy. 3 ; appuaathoa Doppler'* principle, 4 : davlignt e nal photography, 20, 136 ; absorption, 22 ; hydrofiai 62; duplicity of D», 67; theory of corona, 134 ; *p**6** as* double start, 160. J05. 244 ; ****** classification, ISO . n ■»!■***■ sf Nov* Auriga-, 378 ; ■perWaea* as4**av. 443, 476. 512, 690; 'l-issJH * 66 Androtn*da>, 466 j t nebula*. 636 Hufarma. Sir WiUUm and Lady. of calcium, 115. in stars, 176, 191 ; Rigel, 181 ; of Vega. 1 tew. ef INDEX 182; of a aqua*, 232 ; eflect of gravity on stellar spectra, 201. 274, 270 ; epactrograplii.- i(i««ntlK*Uub of trapezium stars, 231, 332; Wolf-tUyet spectrum, 941 ; <|-*-ira of double ittn, 204, 270 ; nteller temperatures, 278 ; oxygen ln0 Ijrss, 53* : unknown ultra-violet nebular rsy. 170, 505 Humphreys and Mob lor, effects of pree- ■ure on spectra, ! Hnnety, observations of Oir-lls, 595 ; glimpse of Nora OnUun. SM Huygens, variability of ? Oygni, 134 ; notice of Orion nebula, 496 Hyades, * non-nebnloiu cluster, 412 Hydrogen, ultra-vfol.-t apei-tnuu, II, 62 ; a chromospherk <*ui»titn«ol, 10, 19, 60, 112, 110, 117 | harmonic relations of spectral lines. .'.2. OS; • second series observed In stare, 64, 1 ?'». 181, 187, 189, 196, 237, 289, 240, 406 s m nebola\ 479 ; escape front earth ■ atmosphere, 66 ; ■[•#< trum truneated in tbe tun, 60 ; invht in sun-arxiLs, 95 ; in fee ales, 101 ; atworpti** enecta in stare, 179, 181. 182, 191. 197, 308, 210; brifht in variable*, 166, 223, 362; in hello m .ur., 220 386; la Wolf-Rayet stare, 237-241 , in .1 Lym\ 338, 839. 840 ; in Nora Aung*. 376 ; in Nora Fernet 390 ; in nelmla\ 470, 478. 488. 600-602. 680. 687 ; triple structure of bright line* id Mire, 224, 225. 238 Hydrogen ntsr*. •p«-<tr«J characteristic*, 179. 182, 187-202. dMolopraent, 272 | tmiperature, 273 lutpdl. structure of a rsy nebula, 442; of sji annular nebula, 492 Id tire, investigation nf eclipsing uteri, 316 ; magnitude of if Cano*>. 371 Iron, absorption in »o1sj spectrum, 80, 40, 41 ; iu spot sperlra, 90, 82, 90 j in sutler spectra, 188, 1*4, 191,210, 212, 220; «pecti»i pfjK>i»i»i-y, 84; bright lines of, in Mm, 226. In x I'ygni, 226 J anion, discovery of i' CyguL. 13 i Jensern, solar photographs, 17, 78, 75; corona nf 1*71. 125 , Frauuhafer llaee in cronal apectraBii 198 Jnvelli*, tu«A.«ures of s pUnstarv nabula, 4 S3 .It- well, variable Fraunbofer line, 87; i-rtn t- "f prrxciir* un we»e length. 88 ; -tru'lur.' <»f Freunli >f« base, 40, 41, 103 ; titan nun- 1 in •*■ in «diNimo*iil»criL- eprcirum, 118; nilatinn of rerarwnr layer, 147 Julia*, eolar phenaminn explained by anciiisJuo* refraction, 147 Kant, nature of tbe cr*ati«» pn-reee, 646 Kapteyti, aUllar •Jletributlia anil -petrel diversity. 178. 643. in K«fl. 174 ; radial velocrttea erf ulr, 177. 470. 476. 403, 493. 499; *p*curoeco|<k Indication of huh tetn- peratare, 181, 201 , bright |(a«a la fiinrtli t> i- spectra, 218 ; «|*c«niia of a Welf-Reyet star, 239 ; hydrogen- eavnlopn of another spar! men. 241 : •pectruuiof rCaeafouet*. 249; 1> Ituce in fl Lyras, 344 ; sAotograuiia of T Tanrt 373; of mUIs, 417, 443, 44 4. 437, 492, 408 j of duets* to Heraaba, 432 | errora of dratifbtatuen, 447 ; double ftebnta. 462; rifted aabala, 460 ; epeetmeoo^Miewiinentoejnilav tlou of e cbula, 409 ; •lrawtnga of planetanee, 470, 478, 479, 490 ; de- scription of Ctal Baboie, 473 , Webb's planetary, 480; ipectrant of a steltar nebula, 4M ; alrurlureof Lyranabnla. 486 ; oontrel -Ui. 487 ; hydrogen sprctraoi In usbulr, 49V, 60*i ; errwinxl photograpb of Onoa neWnla, 601 ; ultra-rioiet ray in spectrum, 60); spec- trum of Trir.J nebula, 510 , neJuple ■tax In, Ml ; photographs of Hind's rartabU nebula, 624. 626 Kepler, laws saounoed by, 1 , prescience of, B ; letter to Herwart, 642 Key, atraelnra of annular n*bul«, 403 Key-hole nebula, relallans to nf iiataf< ■tare. 607 ; exunrUon of ana of Ua parts, 60S | tpectrum, 609 Korea, dseeoeery of a gU.l.ular oloatar, 433 Kirhhall, iulsr|iteUtion Of Frasnaaofer llnea, 18 K ri libofa law, dlarefardetl by solar helium, 93 ; by nebular ganss, 402. 407 Kllakerfuea, parallax of Miear, 290 Knopf, optical rationale nf reversing layer, Knott. nebuUms aspect of IT GanLBonun, 301 Koofc, tanaWlity of H Leonia, 866 K.M. fading or a red star. 874 K.ak.dy. ipeetrum of f f.'aesiopetet, 248; of (I ( trloMi. 360 ;.: i- r_ > \- ■ '; ;;.i <•! | iMBCt) 1-~ \ af 5«0 PROBLEMS IN ASTROI'H\ R Scuti, 248 ; colour* of itam, 255 m I.agnon m-hula, involve! a cluster. 424 Lalaode, observation of 3 Uraic Mojoria, 353 ; of Draco planetary, 474 Laronnt, measure moots of M 11, 410; possible temporary sui in, 411 Lane. oomrUrr Inriua in solar corona, 126 ; healing of gaseous globes through coudensatiou, 272, 273, 276 Langley, bolornetric survey of infra-re*! spectrum, 22, 24 ; selective absorption la aolar atmosphere, 64, 70 ; heat stoppage In terrestrial atmosphere, 05; relation of temperature to spectral energT-curvo, 66 ; bent of aun- spots, 8'J; observation* during solar eclipses, 123, 127 ; multiple star in Tnfld nebula, 511 ; glow of white-hot iron, 532 Laplace, self- absorption of sunlight, 70 ; dark stars, 400 Lassell, star in a double nebula, 454 ; description of a planetary nebula, 481; observations of annular nebula*. 489, 490, 493 : of Trifld nebula, 50V : multiple star in, 511 Le Cbatelier, temperature of the sun, 66 Le (lentil, companion to the Andromeda nebula, 441 Lehmann FUhea, orbit of fi Auriga*, 291 Lewis, spectra of mixed vs pours, 34 Liaio, black -edged prominence, 110; drawing of solar corona, 127 Undcinstiu, obMrvaUons of V Cygni, 359, 361 Littrow, triple nebula, 454 fjvetug and Dewar. spectrum of liquid oxygen, 23 ; heat relations of mas;- n cm urn -lines, 49 ; ipcctral series, S3 ; spectra of rare stmoapheric gases, 114, 120 Lookyer, Sir Norman, application of Popplcr* principle to the euu, 19 ; detection in the sun of carbon and vanadium, 31, 32 ; disappearance of a Fraunlicfer-line, 37 ; photographs of flash ■pectmra, 46; periodical changes in spot spectra, 69 ; solar dissociation, 90,96,114; enhanced lines In cbrocuo- uphcri' ipectrurn, 119; corona of 1 87 1 , 125; wavelength of green coronal ray, 130 ; speetnim of Bellatrii, 191 ; or a Cygni, 193 ; of a An, nils*. 201 ; of 8 asgittos, 025; temperature of ehwtric tpark, 273 ; system of fi Lyno, 339. 323 Loans, O., investigation of ceriam spectrom, 30 ; phnl aqjrs fAI» of cluster in Persen-*, 411 Looped neboiav peculiar fpatrts. C 512 Lord, spectrum of a uniilssiw. IM Latest, pbaeee of V Vai|«cmU. S34 Luut, spectrum of e Castle s(a)ea\ £1 silicon in stars, 1*9 Lvne, 0. variability la lofhi. XT spectrum, 330 ; chaajrv* tat, 080. M 345 ; system, 330-342, 345 . oaosam 345, 340 Lyra, ring naboU in, 484 4-M McClean, photograph of a lalbxrk hat 23 ; spectroscopic coaroaanT of 1 Milky Way, 194% 19tJ, 043 , oi>| in stars, 175. 232, 239 ; State <*■ Acatioo, ISO, 187 ; iiiiiiiranasi helium stars. 181 ; sfssctsal sj— say early stare, 18* ; spirtnajiaas of Cygni, 204 , of Asionss atari. 21 of e Carinas 236 i .yUan «f 0 Lri 339 ; speetnim of i Onoass, 4 44 Madler, corona of 18th JnJy l*0e\ IS satellite of Muar. 291 Magellanic cloade, sasksjj to Way, 187, 242, 844 , Wolf- contained in, 242 ; aeboa*. 013. Magnetism, tertwtnai, c i ri I jj aty «■ eidant with that of aun eftota, 3. 1* sympathetic raaposaao to soaar apl lions, 166-159 Msia, light power, 415 ; rTTiasI as* losity. 417, 146. 1X2 ; n J rtil ah Hffcl ikesaaa » Mason and Smith, nebula, 509 Msunder, prewar* i helium spa-tram, 08 ; strmasri ran-epoU, S3; d oplioalad eaaoarnaana 05 ; white promiBeaesw extensions, 134 ; corooal 135 ; eruptive- nature of 137; movemeata of sant ssssa, Ut solar periodicity. 1&C, 157 . oaasffal Uon of nrbula, 584 Maunder. Mrs., coronal phatosnfl 134 ; nature of promiaaansa, 1ST Maury, Mi-a, ataUar rlsiiltiaassa, U 1S1, 102. 1S3, 185, 184V IS* II 194, 197, 20V, ¥05, 107, 210, IV ipe>tmra of Fomalcavt, poslte spectra, 265, 264 lines in stellar spectra, 20 of 0 Aung*, 291 ; s 339, 340 Vie. blaek hales ta rnerje.1 brldfs*. 79 Mecfaain, aiscmory of oeWla, 619 ZZ 3B INDEX afecdenhaU, characterieetion of aetrc- pbyafca,9 Merope, bright&eea, 41 Sj attcodent nebulas, 4l'V 417; nupeclal vari- ability, 421 ; ■pactrum, 632 Meeder, deeenpUan of Crab nibnla. 518 Metalloid*, la Uiv auu. 29 ; facility of ■pectral efleoatnaot, 34 Metal*, la the tan, 26, 80 ; iu rtnra, 181, 182, 183, 184, 189. UKY !'.»;. 201, 205, tot* ; enilefion by Id alvllcr •poctra, 22fi, 234. 284 ; abeonce from nebula), 27h MicheUon, Uinperature *n<l energy apectnun, <■'. Milky Way, photographic atudy of, 7. 68ft, 640 ; 4 dlaUnctlTa apectrtavopie region, 173, 642 ; frequented by Wolf- Rayet itin, 187, 242, MS . by helium lUn, 196, 286, 548 ; by carbon •tar*. I 221 ; by temporary •tars 396, 402, 543 ; by pnoui Babul*. 398. 606. 644 ; by globular clnrtara, 44ft. 543 : problam of ccuialrnr.tJou, 63ft ; dark opening* in. 540, 641 ; megnJludae of component nUr», 642 Hire, character of ipecLrmn, 186, 232, 223 ; multiple hydrogen ray* to, 234, 225 ; radial motion, 234 ; rednem. 264 ; vicietitudeo detected, 348 ; In- eonatancy ©f their method and amount. 349 Mitchell, hyilrtvn rnectrnm la Orion nebula, 191 Mixer, a apertroecopte »Uuj. 289 ; nature of ej atom, 290 Monek, theory i>f tarapvrarj ntara, 579; preferential rWolUty of white liare, 643 Moon, projectile character. 2; photo- graphically itudied. 7 Mono, drawing uf Iha corona. 133 Motlon-displi. r:i,»n:, uf ipacUBl hum. 4, 5. 286 ; in tbe auu. 19. 38, 42. 106, 108.109,283; in Mlra, 224 ; by rota- tion in atari, 280-283 , lu binary syetema, 2*8. 289, 291, 292, 296 ; In *clipaiag pure, 300. 302, 303, 807 ; in abort- prrirni rariahlpa, 820, 329, 334; in 0 Lyras, 338 -341. 343 Muller, K., double nebula, 463 Muller. 0. and K«ri.pf, varUMlity of PT CyguL S25 J of U Valperalas 834 ; of X Peraei, 3fli» ; pbotnmetnc catalogue of the Pleiade», 431 Myer-, syatan, aj LT Pagan. 332 ; of 0 Lyre-, 341, 342 Ne?gam*ele, photograph* of rleeh ipec- trum, 46; fcnluiui-eheorption in enn- apots, 94 Nebula?, connects! with temporary atare, 884, 304, 895 ; photographic auneye, 448, 449 i Irregular, 504 ; noudeacript, 516-621; variable, 622-630; «U Hon, 544, 645 Nebula, giaaoue, pecalianUea of light, 173, 261, 696. 687; hollua riniealoaa from, 174, 175, 491, 499; nadlaJ velo- cillea, 177, 470, 475, 483. 493, 499; Ike metnoe. of .tare, 271, 460, 486, 490, 496; temperature, 902, 636, 636; foebla luninoaitv, 532 ; tenuity. 683, 634, 636 ; meteoric aypoUioata of coo- caution, 634, 536 Nebula-, watte, difficulty of apeclraJ la eaatlgatioa, 174, 439 l aptrality, 440 446 ; rifted, 447. 448 ; avoidance of Milky Way. 446; double, 462468 ; cluttering tendency, 166 ; probable ■ hi lejej in'" H 'i Nebular pftyeka, ineewarebk from -teller {hyeeas 171 1 oandHtona of progreea, 78,174 Habmlnn. abeorptlre Incapacity. 466. ASS ; deaawr Uiaii hydrugea, 476 ; UtrwrtneJly unknown. 176. 803 NtKnloua etara, ltimiooua eUbiliiT, 106 , llerwael'i aotloe of, 460 , diitiaetloo from planetary aaliula*, 461 ; •pawtra, 162. 465, 667 ; frequently cwnponad. 448-465; -loobtfol inaiancaa. 463-467 ; dealrablt inquiriee, 467, 4*8; ee*j ebeorptt'e ewrroundiega, 583 Neerell, expertaunta on coronal rotation, 13G ; duplicity of Cepella, 294 Nawoomb, ooaeUtutton of the aoUr corona, 135 Nitrogen, eheorptwu • hue* in at^llar apeclra, 176, 181. 191. 195, 232, 235 N'ordeuakiuld, notice of clerite, 66 Nora Andromeda.. 886, ill, 450 Nora AqnlLr. nebular iranafanuatloa. 886 Noia Auriga>, nau4rayyaaa|n Ja^eetigtlioo, 176, 374. 882; raddon rue, 376; taaoriao raaparding. 377-379; aebolar phaea, 379t 361 , llgbt-ourre, 380 Nora t'nrinav raaagaa in apaelnun, 383 Nota Onuuri atnaarlUcn, 26 1 ; apactruni. m Notb Oygai. nabalar tnaafwiaetioau 382 Kore Norma., a4otagrafbat datcorory. 382; na%aaaorne>oaU Into a eehtila. 888 Nora Peraei (1 8871, ffpoctrographic record of amaratioa. 884 Kara Penea (180U eadden riao, 366 ; 390; light curve. 891 ; epeetrai eltetaUaae, 392, 398 ; nabokwa emriroaaiettl. 394. 396 Nora f%agitlar>C ■pectrograpbk rwrda, 886 86 PROBLEMS IN ASTROPHYSICS 582 Olben, electrical theory of cnmoU. 3 Omega nebula, conformation, 611 ; alleged change, 512 OppolMT, froUr Absorption, 71 ; meteoro- 1 theory of the nan, 164 Orbtnsky, measurements of ■ globular cluster. 436 Orion nebula, helium -rev In spectrum. 171. 499; photographic exteiiM' I 100, 495 • 497 ; nuclear aUr - gronp, 230 233, 195 - 407 ; scattered Mara in, 498 ; hydrogen-radiations from, 499-502; unknown ultra-violet IfeM in spectrum, 502, 503 ; suspected variation*. 503 , variable stars in, 604; low mean deniity, 539 Owl nebula, observational history, 472, 478 ; photographs, 473 Oxygen, telluric absorption by. 22, 23 ; pretence in the sun-. 26. 27. 29 ; dark tinea of in stellar spectra, 175, 161, 191,105,232,239,241, 338, 465 Packer, variable stars in cluster. 433 Palmer, distribution of stars In Hcrcales clwter, 432 Parkburat, phases of Y Bootie, 313, 814 ; irregularity of V Geminoruni, 866 ; light-curve of S" Cygni, 367 Psschen, temperature and energy spec* train, 06 Teek, Sir Cuthbert, work at observatory, 254 ; light-curve of 8 Unas Majoria, 363 ; light change of R Lynch, 356 Perelre, description of a tun -spot, 75 ; drawing of a sun-spot, 78 Perrtne. expansion of nebulosity about Nova Pereei, 394 Pcrrotin, colours of double atam, 259, 2G1 Perry, Father, dnrk h«limn-1ine in »un- apot spectra, 94 Perry, Professor, masse* and temperatures of alara, 274 Peter. lavaaureiiicuU of clusters, 160, 426 Photography, advantage*, 3, 5 ; Ian double slit, 9. 18, 50; solar. 17.25, 40 ; chromospberic, 18, 99. 10C. 114. of reversing layer, 45, 46 ; of corona, 189-185; of temporary stare, 175, 876, 382, 387, 888, 302 ; of nebulous stars, 190, 462, 464, 465, 466; Of irregular nebulas, 205, 507, 508. 509, 511. 613-515 ; of Nova Pereei nebula, 394, 895 ; of Pleiades ueUdasiU«, 416-420 ; of white uebiiW, 442-444, 448, 449, 466, 468; of planetary end annular nebulas, 472, 484, 487. 490, 493; of Orion nebula. 406-497 . or variable ncbul*, 626, 629 ; of Milky Photometry, its Pleiades, 421 Photosphere, a temperature. 49, 64 Ktitntion. 62. 63. «" formation, 402 Piaui, nebulosity at M Aacrasj 466, 467 Pickeriog, K. C, di-ovary ef e en hydrogen seriec, 56, JJT #- ■DBarption iii solar »•- spectral cbaracU 174 196; fifth spectrum of Procyoo. MonoearoUt, 234 aUra, 239, 240 epeetra, 265 ; rotstte* ef AM*. 1 eclipses of Algol. 50s, BOS; ft Central of eclipaing atara, 000 ; of U Ccphei, 310; of 316; of S Aatliaa, 341 aeter of V Puppia, 334 ; ef 0 L] 338; light cum of T Aeriraaa 367 ; spectrum of U Osaii— isay 1 of Nova Peraed, 392 ; pbiieegseel Nora Pereei, 368 ; epcarteo of seal Pmeepe, 413; eeerau e* PW 416 ; surmised onaee of of g»Jo**. attlemr tree, 1 oyoo. 203; ef ; ee- Weef 1 PosnpeiiN eft eaw.i U bility, 436 ; cataJosnw of etase In 1 438 ; detection of a-ulUr 482 ; spectrum of 612 Pickering, W. H„ spectrsraa of romencae, 110; pketogrmfsse sat ase* 190 ; of Orion trmpssdtiea ; of eeH Involving nebvksrity. 496 ; — il— of tbe entangled star*. 497 J cetana distance, 498; a^erbr** of 0 nebula, 503 Pigott, diacoverv of R Meati, Corotue, 371 Planetary nebula* criteria of diatiactioq stare, 461, 460 ; Thar sisal ke sea 469 ; radial valocrtiaa, 670, 471. temples structure, 471 472. 474. 532; spectra* 4?«V«7»; nuclear, 480 ; diatneertKst, 644 Plaaamana, ligkt-eaeafe of X Teswv 3 Pleiades, helium spavtra, tSl. 104, i 420 ; eabnleoaly tntolved, 180, 416-420; general stakality 406. 421 ; drifting 415; atypical uebukeaa fewtiKM of real recession frees tfce fugal tandeney. 497 PluvtaeL Frauabefer - line* ■pectrua. 132 m ~ Z s INDEX 6« Pom, Tonabihiy of 8 Una Majicu, 863 ; of B Lapbai. 309 Polaria, ■jw.truBi, 206 ; triple ayatem, 298 ; ■ Pollux, aaUmata of mua, S00 Potto, %hlcur*r nf U Ononle. 860 PlMMipi, ineaiunai o< iiomc'iKBU, 412: thair •pcctra, 413 Pritdunl. |«t.ilUi of (i Aurt**, 291 Proctor, rafmctioa In atta-npoU, 80 ProcjOB, apectral rvUtioaafclpt, 182, 208; mui, 204 ; eami <il<eour* com- panioa. 400 PromlMbMa, coToaaoapbaric o*t«rowUia, 16. lfc\ 101 ; aMoRTa***, 18, 09, 109 ; vuialieu, 102, 108 ; m<«y«in«nt* la, 103. 108- 109; atmetnre, 108. 106, 1011 ; .ltamatrwal ■ttuatima, 108; whJW aiul Mack. 110. 120: apaotram, 116-121 ; rvUUooa will, coronal jeta, 129, 130; ejectiva rbanacWr, 137; moveo.il" in Ut-ituda. 163 Pa pin, corotol.UI dlaaaarffea, 140 Pye, obaervation of ravaraUg layer. 44 Rambant, orbit of fl Anrif*. 391 Kamaay, diacorary of Mam, 29, 68 ; lU alactrlc conductivity. 69 Ran yard, photograpo of a eun epot, 76 ; coronal ■truclcrwa, 128 1 coronal typaa, 128: wmlral atar In l.yra nebula. 1*7: (-information »f Orion nebula. 1 04 all.M >'..'■!■ '»! "tarn i :> Key h>l« nebula. 60? ; dtmoean of nebula . t'A'J ; tlietr tmall mean dainty, 598; 6X4 Ited alarv An tartan, 179. 183, 209; carbon tyj«. I":'. 1»4, 818: VaVwmla in tint. 264-266 ; in llgbt, 862, 370, 374 ; rcl*ti"U of '--•I'-ur-inUnaily (o lenirth •:■' Bfftffjj 368 Reed, halt- in .Ullar llffht-ehaafa, 860 KefrartbaB, nlbvt* uf lu nun. 106-167 Hegulu*, a helium *Ur, 1M rUvanting Uytr, diaoloaura Uuriua; eclijiae*. V, 44 ; poaition in taa a**, 1«, 4«. 181 ; pfcot graphed, 46, 48; analyabi, 17. 4*. 182; Urapantara. 49 ; trun-nuUily. 60 ; alight piiailll in. 61 . pttad raU'mala, 166, 187 IU'-Cm. le\* I t»( «uu tpot*, 80 KiKcb abv-d ■•.- I in by helium. 174, 181, Itfl ; bj •.h-on, 1H3; ina.inoeity, 198 Ititrhey, Mi)«tidiui| nabula round Nora iVr-i, 394 Itittvr, «ii\r m»**« and lain pent urea, 274. 276 Roberta, A. W., eyttaw of Its! RaffUaril, 30" ; dotaatlOa aitd iu*e*ti|ptfion of eclipaiog M8W, SIS. 818. S18 ; phaata of 6 Vepbai, 320; of K TriaDfoll, 324 ; of R* Cantaorl. 831 : of V Pnppta, 334 ; of 8 Arm, 336 ; macnl- tada.rfw Carinas 871 Rnbarta, leaac, pb>Ho»jr»pht of a elrral nebula, 190, 616; of duel an, 4S3, 436 ; of tba AaJmrn-da ewbab, 440; uf other iiaraU, 441, 442: of rtftatl nabuba, 447. 445; of a aabaluua aUr, 466; of Owl nebula, 472, 478; of annular oabulas 480, 490; of TViBd, 609; of On>«a nebula, 511 ; of aonriaacript nebula*. 617, 618, 619, 620 : |ibotofmihlc aaarch (ur a vanJabrd nabula. 626 UmImiwmiu, nl^arTalloo of Ur Owl txtnua, 472 RoaattL tolar tanparaturr, 86 Koaaa, Lord, irnu^nwit of atara In M 37. 410; nabuloaity or 16 Moiio- crrotla, 426 ; parforalad eluatar, 4.1S ; ray nrbnla, 442 ; IjM ik-IkjUt, 44S, 441 645; cometary orbnla, U observation of 68 Andromada, 446 ; Owl nebula, 472, 478; ceatraJ atara in annular nabul*. 480, 469, 498; Crmli nebula, 618 ; conUnua of i B*bul»> 681 Rotation, aular, ■paciroafopicaj I y n»lna.J. 7, 19, 144, 146; from apal- aaovannta, 83, 142, 148; from facaba, 146. 146: attrwrAad aspUna Uoo of anonuliaa. 147 149; taaa- ratical effect* In ■tollar apactra, 280, 281 ; naooaraat to ibaar^iloa. 262 284 | of paaaatar* aaVaaa. 469, 470 Howland, tnvaotiao of aoacai 18 ; raap of aolar ipactrara, 26 ; limtunrtry, 26, 26. 30. 31. 82 ; plwto- (rapUa of laaUllic KjwcUa, 26, 81 ; variable Praanhoferlioe, 97 Ral-iu, tetnparatura and epactral eatergy onrra, 66 kun/a. daplicit? of cWviu . ray, 67 ; faydrofaa - aavwiopo of a atar, 241 ; •pavtnun of Orkaa nebula, 601 Ruga and Paaaaaa, oay^an tnplaA aa aoW apawtnaa. 29 ; apactrai aaviaa, 63, 64 ; ejjectram of balium, 67, 68 Knaaall. B. (X, motatuanu of atara In Jvwwl c I aatar. 414 ; phoUajraphto aad aiaoal ubaaramllowa of Ray-hida nabula. 607. 608 ; u4wtoffrapba of Coal-eack ration. 640 ; of aaboW. 644 Kua— II, H. N , daaaity of eelljNlng itara, 807. 808. 310 Rydbart, rpaclral arriaa. 68; laird aydroffu*. aadoa, 187, 180, 832. 287. 286,240 Habtna, annepot aad inafnatk paatoda, 3. 19 564 Stfank, periodicity of 3 Persei, 370 Sampson, origin of the tolu- rotAtlon, 148 SavSHeff, solar radiation. 68, note Sawyer, vnri&bility of U Opliiuchl, 311 j of B Cuif Mejoria, SIS ; of RX Heroalis, 315 ; of T Vulpocalw, 326 ; luminous outbursts of R Lyra», 368 ; minimum of R Coronre, 372 Seluebcrle, perspective effects in corona, 124; coronal photograph*, 126, 129; ojective theory of corona, 1S7, 165 ; conformation of nebulas, 474, 492 ; photograph of a nebula, 516 Scheiner, tieat-rtslationH of mtujoeaium- Uom, 49, 181, 167, 200. 201 ; locus of general abaorption in Ann, 71 ; tfiinporatnre of the corona, 138; March for electrical vibration* in sunlight, 169 ; carbon bandit in stars, 184 ; constitution of solar atari, 207 ; temperature of electric spsrk, 273 ; incipient brightening of stellar hydro- gen band*, 284 ; photographic catalogue of start in M 13, 438 ; spectrograph of Andromeda nebula. 439 ; photographs of nebula?, 493. 513 ; measurement of ■tars in Orion nebula, 498 ; hydrogen spectrum io nebula;, 499, 602 ' Schiaparelli, colour of Siriue, 256 Sohjallernp, red stars, 256-258 ; obser- vation of 6fi Andromedjs, 466 Schmidt, A., optical theory of the sun, 165. 100 Schmidt, J., colour of Algol, 256 ; low minimum of S Cancri, 306 ; detection of a gronp of variable*. 825 ; fluctua- tions of f Geminornm. 328; periodicity of u Herculls and R Lyne. 868 ; minima of R Corone? and oft AurigK, 872 Sohoofeld, period of R Lyras, 368 ; vari- able nebula, 628 Schultz, central star in Lyra nebnla. 486 Schumann, constitution of Nova Auriga-, 878 Schur, light curve of tj Aqsilss, 321 ; catalogue of stan in Fresepe, 412 Schuster, spectral series, 63 ; variations la the electrical conductivity of epace, 168 Schwab, phasea of U Bagittce, 816 Sohwabe, discovery of sun-spot period, IS Sohwanschild, orbit of fi Aurigw, 291 Sear)*, invisibility of star in M-sonuUr m*rmla, 490 Seccbi. darkening of sun's limb, 70; rosy veils in spot umbra, 77 ; erupt its hypothesis of solar constitution, 166 ; localisation of stellar varieties, 178, 179, 181. 186, 186 ; bright lines (a fourth-typo spectra, 186, 216; spec. PROBLEMS B tmm of a Hercnlia. 211; of Superba," 217 ; of y 249 ; of & Lyra-, *W ; double stan. 200. 241 , in Lyra nebula, 4S6 ; in Gemini, 498 ; Hind's nebula, 623 See, evolution of doable scan, if* 462 ; dementi of Stria* IS* ; » of Sinus, 25ft ; doable a-baha, 4ft Seeliger, selective abaorptiosi 71; »Ur refraetio., 167; hypothesis of N theory or stellar oat bants. 879 Sbackletoo, pbcrtoejmpfe of aw** « trum, 19, 46 Sidereal physic, dedued, 171 6 as hsaatM of aolar payaica, 172; as 177 ; connection with aeeeeeal chanica, 2S7 SiUgrtavee, variable? convexity of spot-uaibrx, 80. vntioo of a prominence, lit ; reea of faenlsa, 146; eruptive ■yye'aaw solar constitution, 165. of Mlra. 186. 228 ; of i 167 i of 0 Lyras. 839 ; < Nora Aarigsa, 879 ; of See* Par 890, 891, 892 Silicon, a constituent of the astaV 0, nf aura, 181, 182, 191. 198, 19ft, 1 232 B9rhssi 'ilic'>u ebwrytioa in. 191; sew* character. 197. 200, 201 ; aaasa < brightness, 198, 199 ; eolow is el quity, 368, 256 ; dcafcy ■itiassss, 4 Smrtn, Admiral, colour* of dee We stt 269. 260 ; gold -daws el aster. 414 red satellite rtar, 404 Smyth, Mam experftaaeato «a m t, M; eaaosn af heat • radiation, HercuUa, 260; redaeae of a 370 Sola, Cotnaa, triaaruWUca wf ** Sagittarius. 494 Solar physics, wide ressfe of. f ; tion, 13; altared Heatcufcal methods and ebaraotee of pay 17. 20, 160; lllastrated by saaan resoarvh. 172 Solar stars, characteristic*. Ill % transit ion from hyeVaawss seat*, 81 giant tpecime**, 20t\ 308 . saw orbs, 206, 207; etara, 207 Spectra, nebular, aifaeaflty gmtfat 178. 174; 440; awaeeae, 476-480, relative strength of 476, 479. 499 .601; of tSomfef a3 INDEX 565 Spectre, etellnr, local di*mltj«(17a, 187, 196 ; cleatirkntioe. 179-138 | banded, 179. 183.184.207. 209-230: with bright linen, 186- 138, 217-420. 223-235, 237- 246, 407, 408; variable, 237, 147-262; ■ ,,.,!..,,-, :';<;, vi;, 2.* 1 . diaaimi larly coupled, 343-249, 370; rnluUrma to colour, 263. 370; evolutionary eup- «wl(iu, 271-278: of Algol variablea. 81d; of <:*i»b*-UI iiruVlN, 52? j of Mm variable*, 340; of Nov., 397 ; of cluetera, 418, 414 ; free from nebo i*r absorption, 6X2; gulncttc type*, MS Spectrography, imporUnro of. 8, 4. 38. 122, 284 ; detection of binary tyiuru by, 369; applied to temporary alara, 370, 884, 888 ; to cluaim, 418 ; to nebula, 439, 474, 80S Speetroe«opU> rrtninea, diecoeeriee, 178, 389-298 ; of dtMmlln light-quality. 344, 396 ; efecle of rotation on, 283 ; nature of evidence regarding tbeli movement*, 388 ; claeeiflcetion, 389 K pert rum. •olar, vutble eeoUou, 21 ; into -red. 24 ; photographic, 26 ; thronged with eheorptloo ■ Una*. 38; ixmiliarttlai, 87-43, 182; telluric. 38, 34 i of eiygvu. 3ft ; of bettnm, 29, 87, 68. 118, 114, 174 | <rf nrks, 31 ; of reversing layer, 44 48 ; of hydrogen, 82-84 | of *oroclum, 80, 190 ; of ■iiu-apota, 88-98 ; of fatal*. 9fl, 100 ; of chroraiMphere and promt uencee, 1)2-121, 143 | of tli- corona, I'O i,.V. \M SfH-^tnim analyst*. Import of, to aetr»- n.:iiiv, i ; to a-.lar |.liv»ii, 14 Hpam,' lijrbt- change of 8 Anllur. 331 Jtpica. a epeciroecoplc binary. 292 Spirit nebula, rumple*, 440-448, 487 , prwalMifc, 443 , eiplaaiv* theory, 448 1 Mtuul.u -luplidtf, 483 Bpttoltfi 'IrawtBf* (>f nebula. 466. 487, 164, 830 ; mvaturamenui of uebul*. 4831 . invieiblllty of central iter In Lyra net 'iila, 487 Bp i> r, ■b.fljnga of sua epot rone*, 181, 189 Star . Inetere, globular, atroelttiel plan. 40V, I2fl ; eiawplm. 429-430 : nun- uol«iloue, 433, ueeto of variable*, 494, 186, 884-488 . frequent the NUky W»y, 448 Hur *■ luelere, irregular, eoojormntloo, 40W ; example*. 410-414; nebulous, 423-427 HUn, claaaiQco'Joo, 179; evolution, 271- 279; raUtlott, 280 288 .Stefan, law of radUUoa, 84 Stellar natal** limit*! to tba Milky Way. 844 Htephan, achuloae alar. 407 ; diaoov-ert of an.bala.479 ■bona, Onnowt, aapeet of Orion nebula, 603 ; varying bright ne*. of onntnlnal etara, 804 Htnney, »p*Hral eerie*, 83 i eaonpe of gaaa* from planetary atmoapberan, 88; rompoiition of phctoavhnr*. 03 Strut vuotf, rotation of tba wn, 83 ; of faculae, 148, 147 ; omnia «f fe Pleiadee, 418 ; netmloatteaa of tba Pleiad**, 418 Strove, 0., dietaioo of y Andromeda, 244 ; raata of * Caeelopeon, 248 ; ob- ■erraUoD ot ut-uuulax nebula, 490 ; •lianppearunoe of a star in Orbs nebula, 804 ; diarovery of a I— iporary ubnla, 824 Strure, W.t colour* of double »t*rvt 289, 281 : duplicity of Atlaa. 421; tnpllclty of 18 MooocaruOa. 420 Sun, new vie w« regardlngi 1 4, 16; append- age-, 18; ■beaatotry, 18, 21, 26-34. 183; apectral pMoHarittaa, 34-U, 102, 163; connmnatWw, 02, 101 , gvnaraJ atmoapbarw abnorptloB. 04, 46, 09. 70. 71; radUUon, 04. 06\ 88, 161. 168 ; uMapmtnns 46-47, 48 ; lAoto- rpnerif vol. 71, 72; a bright line •bar, 121, 184; mode of rotation, 143 149. 181 ; perlodlritv, 160180, 143 j ■ vnrubU ftar. 161. 342 ; tbeoriao of nonatltutioa, 104-147; a eolitmry body, 172, 382 ; motion in apace. 192, 410 , etagv of dweloproent, 974 Son ■pot*, periodicity, 3. 13, 180 UJ doubta regarding, B, 8«. 37 ; •pertn, 72. 0S97, 183. 196; ntractural feml- uraa, 78. 76-77 ; ralntlona to facnkn. 74, 181 ; grooplnn 77 79, 88 ; quae Uoa «f level, 79-M, 88; bant emtaeio**, 81. 82, 184 ; movemanta, 83 86. 94, 182> 144 | iHoieiMiona, 86; ehamutry, 91 ; aoarcity in aeventaenlb eectary, 164; mngualc relatione, 164 1M nalare and origin. 102, 104; rnfrnatfva effect* In, 107 Hwifl, black linen in promlaenaea, 110 | nalmloalty in Monnonroa, 426; hnb- llna nebabn. 442; double nebula, 465. 457 ; nebular grou|ia, 468 ; nebnlama aUra, 442, 443; new fenturv* In Trtfal an>l Omcgn nebula-, 822 ; obeannlkw of a variable nebula, 627 flykon, meantime nf tba inn'i diameter, 74 Tnockinl, •laylight vilant of chroma - •pbere, 109| vbltr pramlnoaoae, 1 10, 120; coronal relation* of pvomin*noem. 129; magnetii- InfltieiKevofthecbi •share, 167 566 PROBLEMS IN ASTROPHYSICS Telluric sbeorplion, 22-S6 Tetnpel, discovery of M crops nebola, 416, 522; drawing of a spiral nebula, 443 ; Cuacornac '* nabula, 623 ; obser- vation of Struve's temporary nebula, 526 Temperature, of reversing layer, 49 ; re- lation* of lo hydrogen *pectrum, 64, 201 ; in solar photosphere, 63-67, 69 ; Id jun-ipoU, 92, 96, 104 ; in solar corona. 138, 140 : in stars. 19a 196. 199-201, 278, 274; in nebula:. 602, M Temporary nebula?, 624, 626, 628, 629 Temporary Stan, spectral character, 176, 397 ; recent apparitions, 375- 390 ; photographic' discoveries, 382- 887 ; "umuiary of facta regard inn, 390-398 ; galactio proclivities. 396, 402, 643 Theodoras, observation of u Oirinst, 371 Thome, colour of e ilarinr, 371 Thomson, electrical aflinrUrs of hydrogen- lines, 112 Tlwerand, disturbance* of Algol, 306, 300 ; of U Cophei, 310 Titanium, absorption by in the mm, 32, 49; in epota, 91, 92; in etar*. 19l!. 193, 198, 226, 232 | bright linn of in (lean and'chrouioaphcric vpectra, 47, 118 Toucani, 47, globular dorter, 431, 436 Tripexium atari, oompoaition of group, 230 ; spectrum. 231, 232. 498. 632 ; iucoiMpiciiuusly variable, 406 ; photo- graphed, 496 ; proper motion, 497, 498 Trifid nebula, nuclear multiple star, 40(1, 510; conformation, 609, 510; spec. mini. 610 Trouvelol, veiled upota, 102 ; observa- tion* of prominence*, 1 06, 1 10 Trowbridge, spectroscopic experiment*, 34 Trowbridge and flntehins, carbon in the sun, 32 Tuner, photographs of the corona in polariaed light, 1 32 Tattle, discovery of a variable nebula, 627 Vanadium, a constituent of the sua, 32, 49; of prosnlaeocee. 119; of Stria*, 198 ; prominence of ebeorpttou in apot-apectra, 91, 92 ; emiauon In y •Caaaiopaiie, 234, 249 Variable nebula-, evasive of recognition, 622 ; authentic examples. 623-628 ; problem of, 629 Variable stare, aolar analogy, 161, 176, 362, 406 ; their helium emission*, 176, 326, 2*28 ; ope© W> 1 1 ■ anV, 1 176; ia clatter*, 177. 319, 331 1 433-43S ; with fourthly?*) *f*S 216.368-360; with bstgnt^a** as %la**1l,lMMMari r.tLoul spectra, 246-243 ; mttaee*. UN 862, 368 ; of abort patted. SIM 404; of long period, 947-4*3.1 gnlar. 363-374. 405 spectrum and period, 404-461 Variable stellar spectra, an taerpfcna phenomenon. 227 ; example*. 24*3 838, 330, 344 Vega, RpootrograpbeU. 1 83 ; apeetruni, 197, 198, 201 ; 200 Very, pbolospheric nebulous formatioa round N* 396 Vogal,aa,tpeciroBrapJikis lie*** of radial motion, 4 ; aolar aSusajii absorption. 70. 71 ; holms* etar*. 1! 181 ; stellar cJaael rtcaUioxt, 1M. 11 carbon stars, 184, 277 ; date* esae* 211, 277 ; spectrum of Mirsx, 30; a WoLT-Rayet star. 289 ; «s* B Oss nonim.246; of y (asiupe—. 246 ; It Crgni. 265 ; of M Hernias. * ofCapella, 294; «f 0 Lym. S3*, X colour of y Dclphini, 200; Altair, 281; perioa of duplicity of Spies, 293 ; of Nora Aarig*. 378 ; r*4asl of Nora Perse*. 390 ; ftrvctxsr* sf planetary nebula, 471 ; *4«arvan*aa* annular nobaha, 487, 490, 4*3 - * visibility of a nehuba, £88 Vogel, H. W.( ftfth hy4rexea*vlaxta, S3 Wads worth, small apertures far MM photography, 423, 496 Webb, colour* of double itm, 269, X dieoovery of a planetary ReWla. 479 Weies, coronal struct ore, 136 Well*. Mies, discovery of W I Met* 315; of 8» CygnU 364 WeenWlL pboiosssstrk ■!■■— I ef Pegasi, 332 Wealey, study of, aa-1 dr*wun*» be coronal photograph*. 125, 1*4, IS 135 Wiedemann, effect* of In sail lessee* m. S« 397 Wilnyn-ki. »»4* of soesr iHiHi^ lil William*. SUaley, dsnovef*- ef eaass Ess) «tai% 316 : of V Pupfjie, *** Willing, rotation of farxuu*, lU.Wtj ■uu. 148. 