1895.] On the new Gas obtained from Uraninite. 115 



I no\v proceed to show that the same conclusion holds good for the 

 gases obtained by Professors Ramsay and Cleve from cleveite. 



For this purpose, as the final measures of the lines of the gas as 

 obtained from cleveite by Professors Ramsay and Cleve have not yet 

 been published, I take those given by Crookes,* and Cleve, f as observed 

 by Thalen. These are as follows, omitting the yellow Hue : 



Crookee. Thalen. 



6677 

 568-05 

 566-41 

 516-12 



5048 



5016 

 500-81 



4922 

 480-63 



4713-5 



The most definite and striking result so far obtained is that in the 

 spectra of the minerals giving the yellow line I have so far examined, 

 I have never once seen the lines recorded by Crookes and Thalen in 

 the blue. This demonstrates that the gas obtained from certain 

 specimens of cl&veite by chemical methods is vastly different from 

 that obtained by my method from certain specimens of broggerite, 

 and since, from the point of view of the blue lines, the spectrum of 

 the gas obtained from cleveite is more complex than that of broggerite, 

 the gas itself cannot be more simple. 



Even the blue lines themselves, instead of appealing en bloc, vary 

 enormously in the sun, the appearances being 



4922 (4921-3) = 30 times. 

 4713 (4712-5) = twice. 



These are not the only facts which can be adduced to suggest that 

 the gas from cleveite is as complex as that from broggerite, but 

 while, on the one hand, the simple nature of the gases obtained by 

 Professors Ramsay and Cleve, and by myself, must be given up, 

 reasoning on spectroscopic lines, the observations I have already 

 made on several minerals indicate that the gases composing the 

 mixtures are by no means the only ones we may hope to obtain. 



This part of the inquiry will be more specially considered in a 

 subsequent communication. 



I may remark in conclusion, that in this preliminary inquiry no 



* ' Nature,' vol. 51, p. 544. 



t ' Comptes Rendufl,' April 16, p. 835. 



