84 PROFESSOR J. N. LOCKYER ON THE PHOTOGRAPHIC 
Table III. shows in a complete form the details of the coincidences of the lines in 
the spectrum of the Westgate photograph of the Orion nebula with those of 
planetary nebule and bright-line stars, as given by PickERING and CAMPBELL. 
Only those lines of the nebula which show coincidences are included in this table, 
but the spectra of the planetary nebulee and bright-line stars are tabulated in full.* 
it will be seen that all the lines of the planetary nebule, photographed by 
PICKERING, appear in the Orion nebula, while of the twenty lines photographed by 
CAMPBELL, twelve are present. Of fifteen lines in the spectra of the bright-line 
stars, eleven appear in the nebula. 
Tase II1.—Comparison of Orion Nebula with Planetary Nebulze and Bright-line 





Stars. 
Planetary nebule. Planetary Bright-line Bright-line Bright-line 
Orion nebula. (CAMPBELL.) nebule. stars, Type I.| stars, Type II. | stars, Type III. 
(Rowrann’s Seale.) | (Prckerinc.) | (PICKERING.) (PICKERING. ) (PICKERING. ) 
3868 (4) 3867-8 
3887 (4) 3888 388 389 389 
3949 (1) Ae af 395 ih 395 
3968 (5) | 3969 397 398 397 
4025 (3) 4026 He 402 4.02 
4067 (2) 4.067 ae 406 406 407 
4101 (6) 4102 410 410 410 
4120 (1) an ie oye a 412 
4204 (1) be “a 420 420 421 
4340 (6) ABAL 434 4.34 434 434 
sis 4363-4 
4389 (2) 4390 
4426 (2 a6 ae ate se 443 
4471 (4) 4472-3 447 ie 44.7 
bie os ae 451 451 
Se 454 455 455 
4574. 
4.595 
4610 
4631-40 462 464 464 
4663 
ae 4686-8 25 469 469 
4715 (2) 4714-6 470 
i 4743 
4861 (6) 4862 486 486 486 
4957 (4) 4958 
5006°5 (5) 5007 501 






* Professor PickerinG has been good enough to furnish me with glass copies of his beautiful photo- 
graphs of the spectra of some of the bright-line stars. The positions of the various lines which he 
gives are in the main confirmed by the new measures which have been made at Kensington. I am in 
communication with him as to additional lines which have been mapped. 
[In consequence of the delay in printing this paper, I am enabled to state that Professor CAMPBELL has 
communicated some most important observations to ‘ Astr. and Ast.-Phys.,’ 1894, p. 448, on the Wotr- 
Rayer stars, which show that the number of coincidences with lines in the nebula of Orion and planetary 
nebule is increased by 7.—Note added 4.1.95. ] 
