398 



Intelligence and Miscellaneous Articles. 



As is seen, the agreement is perfectly satisfactory ; let us add 

 that it is equally so in the details, such as the presence of a fainter 

 shaded line between 1 and 2, and of two shaded bands in the red 

 field. Hence it is impossible to doubt that the spectrum No. 2 be- 

 longs to the oxide of carbon. 



There now remains spectrum No. 3. This no more than the other 

 belongs to oxygen. Perhaps some lines of the known spectrum of 

 oxygen are found in it ; but most of the lines belong to chlorine. 

 This assertion is put beyond doubt by the following Table, which 

 contains the wave-lengths of the chlorine-spectrum and those of 

 spectrum No. 3. 



Supposed Spectrum of Oxygen, No. 3. 



1. 



A large group .... - 



" the first line . . 



5461 



5460 ] 





k the last line . . 



5404 



5399 \ Chlorine. 







'the first line . . 



5215 



5213 J 



2. 



A large group .... - 



the middle line; 



very bright . . 



k the last line . . 



I 5152 



5090 



I Oxygen ? 





Group of six series . - 



r the first 



4938 



4940^ 



3. 



. the last 



4893 



4895 





4. 



A large group . . . 



the last line . . 



4805 < 



'4820 



4808 



)>Chlorine. 











4793 | 







' the first 



4652 



4647J 



5. 



Group of three lines - 



the second. . . . 



4644 



4642 Oxygen. 







the third .... 



4637 



4630 Chlorine. 



6. 



A violet line 





4418 

 4621 



4417 Oxygen, 

 p 



7. 



A violet line ....... 





The result of the above examination will therefore be, that we 

 know not yet any other oxygen-spectrum than the one observed by 

 me in 1853, and which has subsequently been studied with great 

 care by Pliicker. 



I ask permission to add a few words on the action exerted by 

 magnetism on the spectra of gases ; these considerations have an 

 intimate connexion with what precedes. Under the influence of this 

 action the spectrum assumes, according to M. Treve, a quite differ- 

 ent aspect ; so that we should be able to produce not merely by a 

 rise of temperature, but also by magnetism, the multiple spectra 

 which, in the opinion of divers savants, present themselves with 

 gases. This is correct in several respects ; but the explanation of 

 the phenomenon appears to me to be different from that which has 

 been given of it. In fact the modification in the appearance of the 

 spectra depends simply on this — that the action of magnetism causes, 

 at the incandescent state, the occurrence of other substances or other 

 combinations. In certain cases the effect of magnetism may be com- 

 pared almost to that which is produced by the addition of a condenser 

 to the Ruhmkorff coil ; but magnetism appears also to exert a sort 

 of chemical action, obstructing the production of certain combina- 

 tions, and facilitating the production of others. 



