THE SOLAR SPECTRUM AT THE DATE 1877-1878. 295 
Appear- PLACE- Differences. 
Intensity ance by DATA, |Chemical-origin-|} Concluded Sa 
é _”.,| graphical | Micrometer from data, from WAV k- = 
Object: ebeer ved aeuerally a black, fixed pace o compara-| Reading. Angstrom’s Angstrom, NUMBER- || 2 3 3 
3 of line. tive Grating Nor-| Thalen, &c. PLACE, per || 3 2 g 
* | symbol. Rey. mal Solar British Inch. || § 5 $ 
Spectrum. |ga} 4 
Strong line, . 2° | 57°323 35 405 7 
Strong line, 17 | 57350 Telluric 85 422 rl 
| Fine line, . il 57°366 watery 35 433 13 
Do. 1 | 57 ‘381 vapour. 35 446 9 
Do. 1 | 57°395 35 455 iS 
Ge Do: 1 | 577413 35 468 35 468 30 
The above bracketed lines, 35 243 to 35 468 W.-N., form the band of little a itself; a terrestrial water-vapour 
group, of which the lines increase so in both number and blackness, with a low Sun and in warm, moist weather, as 
to make the whole band one black club, excepting the light chink in the middle; though that may also be blocked 
at last. In this condition the so-called little a, and its preliminary band, look gigantic even as compared with great 
A and its preliminary band ; though with a high Sun, great A is the manic and ‘blaokest line in the whole spectrum. 
From this point begin the observations of 1878, at Campolide, near Lisbon, with a Solar Spectroscope, 3 prisms. 
Dispersion= 28°, A to H; and a telescope with mag.-power=20. Date=June 21. Time=9h. 50m. A.M. The Red 
colour of Continuous Spectrum i is a glorious background for the delineation of the black spectral lines. 
Suspicion of fine line or band, 0°2 12087 35 498 | li 
Do. graduating to left, . 0°2 re eelonag 35 509 18 
Suspected fine line, . 0-2 ' 12°181 35 527 14 
Fine line certain, ie | 12-228 35 541 2 35 541 27 
Suspected fine line, 0°3 : 12°296 35 568 24 
Do. do. 0°3 : 12°355 35 592 
Very fine line, - 0-6 12°450 35 627 
Fine line, 1:0 | 12°560 35 671 
57 
Suspected fine line, 0°5 12°700 35 728 3 
Do. do. 0°5 12°708 35 731 
Do. do. 0-4 12'756 35 750 a 
Do. do. 0°5 12950 35 830 34 
Do. do. 0'4 13°035 ; 35 864 
32 
Finest line, 06 | 137118 35 896 39 
0. ; 1:0 | 13198 35 928 | 
Suspected fine line, 0:5 : | 13-239 35 943 . 
Do. do. 0°5 13°242 35 947 
Do. do. 0-5 13:380 36 000 2p 
Fine line, double—1st line, oz || 1 13-482 SEGRE pares 36 038) || ¢ = 
2d line, Oe! leh yl 13-504 Aine 36 046 | 
Suspected fine line, 0°5 13°590 36 078 : 
2 
Fine line, double—l1st line, 0°8 13°661 36 108 36 105 
| 1 
2nd line, 06 | | 13°693 36 118 36 116 
8 
Suspected fine line, 0-4 13°720 36 124 
30 
, pists double be but fe - ! es nates Mellarie Pee 
= ban? He pon watery 24 
4 Badlines 6° 4. 1 Wee Nee 13°880 |- 36171 Gipotls 36 176 2 
| Strongest line yet, but By, : ; 3 HIE 13°963 36 214 36 210 99 
i Fine line, hazy, ap oe a: | 14080 | 36240 36 236 a 
Strong line of a band, but hazy, : 3 Fa 14115 36 265 36 263 41 
il pee iat also pate . : 2 AE i a aie ee A ay 20 
ess strong sti . : : AE 27 2 watery 2 
q Less still, ‘ ae Bn pee) rr: a: | 14350 | 36343 | vapour. 36 348 es 
5 Very faint and close, ; F é 0°3 ae 14°380 36 362 36 360 36 
_— Hazy band, graduating down to right ; 36 396 
ie hand—beginning, ae ae ‘|t 15 i } ae ao cule 36 414 | 18 93 
b Cudkohmrnnn coe ery iy 
a 36 437 17 
Suspected fine line, . 3 : ‘ 0°5 : 14600 36 437 36 454 
: 19 
i. Domdo a) 45). OD : | 14-632 
sh Fine line, double, sharp—Ist line, . | 0-7 |) } ,, 14:673 36 471 36 473 é 
ae 'F 2nd line, . 07 | 14°687 36 477 21 
= - 
