426 



NA TURE 



[March 4, 1886 



now appears that one of the markings corresponds to the Maia 

 nebula. The other irregularities seem to afford indications of 

 the Merope nebula. There is also a faint narrow streak of 

 light projecting from Electra on the following side. 



Prof. L.angley on the Emission-Spectra of Bodies at 

 Low Temperatures. — Prof. Langley having traced the solar 

 spectrum in the infra-red so far as \ = 00027mm., where it sud- 

 denly ceased, has since examined the emission-spectra of vaiious 

 terrestrial substances at temperatures from that of fusing plati- 

 num to that of melting ice, and more particularly of tempera- 

 tares corresponding to the ordinary conditions of the soil. The 

 result of his observations has been to show that the maximum 

 of heat from cold and black bodies has in every case a wave- 

 length greater than 0'0027mm., — greater, that is to say, than 

 that of the lowest solar heat which reaches us ; and that further, 

 that part of these spectra which has a greater wave-length than 

 that of the point of maximum, represents a larger total amount of 

 heatthanthe paitwithshortervvavedength. Prof. Langley believes 

 that he has been able, by means of his bolometer, to trace out the 

 emission-spectra of cold bodies so far as A = o'oi5omra., a wave- 

 length more than twenty times as great as that which Newton 

 found for the lower limit of the spectrum, viz. X = o-ooo7mm. 



Fabry's Comet. — Dr. H. Oppenheim has computed the 

 following fresh elements and ephemeris for this comet : — 

 T= 18S6 April 5-5398 Berlin Mean Time 



(.1 = 126 50 27 '6 1 

 ft = 36 19 54'o ,• 1886-0. 

 i = 82 n 15-0 ) 

 log? = 9-804021 



Ephemeris for Berlin Midnight 

 -A. Decl. Log. r 



March 7 



31 19-6 N 



32 29S 



33 42-0 



34 54-6 N 

 The brightness on December 2 is taken as unity. 

 Barnard's Comet. — The following ephemeris by 



Krueger is in continuation of that given in Natu 

 February 18, p. 376 : — 



For Berlin Midnight 



Dr, 



Log. 





ASTRONOMICAL PHENOMENA FOR THE 



IVEEK 18S6 MARCH 7-13 



/"pOR the reckoning of time the civil day, commencing at 



^ Greenwich mean midnight, counting the hours on to 24, 



is here employed.) 



Al Greenwich on March 7 

 Sun rises, 6h. 34m. ; souths, I2h. iim. lO'os. ; sets, I7h. 48m. ; 

 decl. on meridian, 5° 11' S. : Sidereal Time at Sunset, 

 4h. 49m. 

 Moon (two days after New) rises, 7h. l6m. ; souths, I3h. 21m. ; 

 sets, I9h. 36m. ; decl. on meridian, 0° 28' N. 



Occultations of Stars by the Moon (visible at Greenwich) 



Corresponding 

 March Star Mag. Disap. Reap. ^,"|'"ri°"t "f"/ 



inverted image 

 h. m. h. m. „ 



8 ... B.A.C. 408 ... 6J ... 18 II near approach 54 — 



9 ... 64 Ceti 6 ... 17 31 ... 18 38 ... 118 342 



9 •■• I'Ceti 4-4 ... 18 35 ... 19 39 ... 156 310 



13 ... 130 Tauri 6 ... 16 49 ... 18 I ... 91 253 



Saturn, March 7. — -Oater major axis of outer ring 43"-o ; 

 outer minor axis of outer ring i9"-3 ; southern surface visible. 

 March h. 



10 ... 2 .. Venus stationary. 



Mar. 10, o o n 



8, 4 50 m 



M signifies 



Meteor Showers 

 Two showers may be looked for on March 7, viz near 7 Libras, 

 R..\. 233°, Decl. 18° S. ; and near 7 Herculis, R.A. 244°, Decl. 

 15" N. Other showers of the week : — Near e Cassiopeife, R.A. 

 36°, Decl. 67° N. ; from Virgo, R.A. 190°, Decl. 1° N. ; from 

 Cepheus, R.A. 300°, Decl. 80° N. 



Stars with Remarkable Spectra 



N.1 



:ofSt: 



124 Schjellerup . 

 132 Schjellerup . 

 D.M. +6S°-6i7 . 

 136 .Schjellerup . 

 56 Leonis ... 

 R Crateris ... 

 01 Virginis ... 

 145 Schjellerup . 

 152 Schjellerup . 

 155/' Schjellerup 

 40 Comae Ber. . 



THE SUN AND STARS' 



First Conclusions 

 'T'HE view of the solar constitution, which was based upon 

 •'■ the early work to which I have referred — work which dates 

 from abDut the year i860, and is therefore about a quarter 

 of a century old — the view which grouped together, and 

 endeavoured to make a complete story of all the facts which 

 were known then, was this : the chemical substances which 

 had been found to exist in the sun's atmosphere existed quite 

 close — relatively quite close at all events — to the photosphere. 

 When subsequent work demonstrated the existence of hydrogen 

 to a con iderable height above this photospheric envelope, as 

 I shall show presently, the idea was suggested that these 

 chemical substances existed in the atmosphere, not pell-mell, 

 not without order, because Nature is always full of the most 

 exquisite order, but in the sequence of their vapour- densities, so 

 that a very heavy vapour would be found low down in the atmo- 

 sphere, and a very light one like hydrogen would be high up. 



It was at first suggested that gaseous diffusion would prevent 

 such a sorting out, until it was pointed out by an American 

 mathematician, Prof. Pierce, that it was a good deal to ask that 

 diffusion should act along a radius something like a million 

 of miles long, and indeed he showed that it would not. 



Before we go farther, I give tables of the different 

 substances which so far have been traced in the sun's atmo- 

 sphere by means of their spectral lines. The first gives the 

 substances according to the results obtained by Kirchhoff, 



' A Course of Lectures to Working Men delivered by J. Norman Lockyer. 

 F.R.S., at the Museum of Practical Geology. Revised from shorthand 

 notes. Continued from p. 403. 



