Intelligence and Miscellaneous Articles. 149 



The statements that leaves are torn and separated from the stem 

 by the mere impact of the rain, in a still atmosphere, that upright 

 leafy plants are shattered, and the like, depend on errors. — Wiener 

 Ber'ichte, November 21, 1895. 



ON THREE DIFFEREN TSPECTRA OF ARGON. BY DR. J. M. EDER 

 AND E. VALENTA, OF VIENNA. 



In this paper it is demonstrated that besides the "red" and 

 " blue " argon spectrum discovered by Crookes, there is a third 

 separate spectrum of argon which is characterized by different lines 

 as well as by partial displacement of certain groups of lines toward 

 the red. The authors describe also the spectrum of the glow-light 

 at the + and — poles of the tubes filled with argon. — Wiener 

 Berichte, December 19, 1895. 



ON THE RED SPECTRUM OF ARGON. BY DR. J. M. EDER AND 

 E. VALENTA. 



Through the kindness of Lord Eayleigh we became possessed of 

 some argon gas which was very carefully filled into vacuum-tubes 

 by Hr. Gloetze in Leipzig. The pressure in those tubes which we 

 used for our investigations amounted to 1-3 millim. For the 

 purpose of analysis by the spectrum, we used a very powerful con- 

 cave grating of f metre curvature, and the photographic method. 

 We measured the spectrum of the second order and referred the 

 wave-length to the lines on Eowland's standards. We examined 

 the red-and-blue argon spectrum which was obtained in accord- 

 ance with the statements of Mr. Crookes, with feeble sparks 

 without ley den-jars or with sparks from the jars themselves. 



Eor the red argon spectrum we obtained the following numbers. 

 The lines marked with a star are also present in the blue argon 

 spectrum ; the other lines are characteristic of the red spectrum itself . 

 As specially characteristic lines of the red spectrum may be men- 

 tioned the principal lines A=4628-56, 4596*22, 4522*49, 4510-85, 

 4300-18, 4272-27,4259-42, 4251-25, especially the groups 4200-76, 

 4198-42, 4182-07, 4164-36, 4158-63, and, further, 4044-56, 

 3949-13, 3834-83. This, of course, only applies to the region 

 examined by us, and we shall shortly publish further measure- 

 ments in the Memoirs of the Vienna Academy. It may be 

 remarked that the red argon spectrum is resolved if the double line 



X \ 41QA.75 appears well separated. If the blue and the red 



argon spectrum belong to two elements, which is by no means 

 improbable, the above lines would be the characteristic principal 

 ones. 



We give the following preliminary list for the region \ = 5060 

 to \=3319, in which i is the intensity of the lines (the feeblest 

 = 1, the strongest =10). 



