of Chemical Operations. 431 



" So far as I know, nitrogen, phosphorus, arsenic, antimony, 

 boron, chlorine, iodine, bromine, have not been found in the 

 sun. In one paper Lockyer suspects iodine. Dr. Miller and 

 I found coincidence of three lines of antimony with three lines 

 in aldebaran. Though this observation would show conside- 

 rable probability of antimony in star, I do not think the spec- 

 troscope (two dense prisms of flint glass) was sufficiently 

 powerful to make its existence there certain. In the case of 

 nitrogen, no coincidence was observed in any of the stars. In 

 my paper in the Transactions of the Royal Society on Spectra 

 of Nebulae, I show coincidence of principal line with the strong 

 line in spectrum of nitrogen. Now this line of nitrogen is a 

 double one; and I was not at first able to be certain if the line 

 in the nebula was similarly double. Subsequently with the 

 powerful spectroscope I used for the motions of stars, I was 

 able to make a certain determination of this point (Proceedings 

 E. S. 1872, p. 385). I found the line in the nebula single and 

 coincident with the middle of the less refrangible of the com- 

 ponents of the double line 



Mtrogen. Red. 



Nebula. 



I say "middle " because line in the nebula is narrower and more 

 defined than either of the two lines forming the double line. 

 I made experiments to see if under any conditions of pressure 

 and temperature the more refrangible of the two lines fades 

 out, so as to leave only the one with which the line in the 

 nebula is coincident. I did not succeed. So the matter stands: 

 — Is nitrogen compound ? Are there any conditions under 

 which the one line only appears ? Has the line in the nebula 

 no real connexion with nitrogen further than being sensibly 

 of the same refrangibility " ? 



Now we must either consider that the matter of these ele- 

 ments so abundant on the earth does not exist in the sun or 

 stars (which is hardly probable), or that they have passed into 

 forms of combination in which they cannot be recognized by 

 the spectroscope (which is also hardly admissible at that ele- 

 vated temperature), or that they have been decomposed. 



Second Note of M. A. Naquet. 



Sir B. C. Brodie replies victoriously to the principal objec- 

 tion which we brought against him, and begs us to suspend 

 our judgment on the second objection. We will therefore 

 await the new memoir which his last sentence allows us to 

 expect. 



2K2 



