Chemistry and Physics. 67 



Lack of space necessitates the omission of even a bare statement 

 of many important observations recorded with respect to the action 

 of glowing nitrogen on compound bodies. Nevertheless, atten- 

 tion must be called to two noteworthy cases. 



Manganese dioxide and copper oxide are fatal to the glow. 

 " The analogy to the known destruction of ozone by these sub- 

 stances cannot fail to attract attention." 



Nitric oxide, when allowed to mix with the active nitrogen, 

 shows a very strange behavior. A greenish flame, possessing a 

 continuous spectrum, is produced and heat is developed at the 

 point of confluence. To test whether any gas condensable at 

 — 1S0° C. was produced, the gases from the flame were led 

 through a U-tube cooled in liquid air, and a dark blue substance 

 was condensed out. This melted to an indigo-blue liquid, and 

 finally revealed itself as nitrogen peroxide by evaporating off into 

 an orange gas, soluble in caustic alkali. Repeating the experi- 

 ment without exciting the electric discharge led to the formation 

 of no nitrogen peroxide. Strutt says : "It is very surprising that 

 a reaction between nitrogen and nitric oxide should lead to the 

 formation of a substance, not less, but more oxidized than 

 the latter." — Proceedings Roy. Soc, lxxxv, May, 1911. 



h. s. u. 



7. On Extremely Long Waves, emitted by the Quartz-Mercury 

 Lamp. — A brief account of a paper by Rubens and Wood, on this 

 subject, was given in the Maj r number of this Journal (pp. 456, 

 45*7). The investigation has been continued by Rubens and 

 von Baeyer. 



The apparatus used and the method of experimenting were the 

 same as in the earlier work. Strong Leyden-jar sparks between 

 electrodes of aluminum, bismuth, cadmium, iron, platinum, and 

 zinc were first tried, but radiations of greater wave-length than 

 those formerly obtained with a Welsbach mantle — 108/x — were 

 not found. "A comparatively very strong long-waved radiation 

 was, however, obtained with the quartz-mercury lamp, especially 

 at higher consumption of energy." With a current of 4 amperes 

 on 100 volts, the arc being about 80 mm long, a deflection of more 

 than 50 mm appeared in the micro-radiometer. A ray-filter of 

 black cardboard, about - 38 mm thick, proved most efficient for the 

 isolation of the very long waves. . 



The authors proved that the longest waves are emitted by the 

 mercury arc and not by the quartz walls of the lamp. The mean 

 wave-length obtained was about 314/u., or nearly 0'Z mm . Thus the 

 infra-red spectrum sustains another enlargement of 1*5 octaves. 

 A table of percentages of energy transmitted by seventeen useful 

 substances is given, both for the Welsbach radiations, 108|ix, and 

 for the mercury arc, 314/u. — Phil. Mag. (6), xxi, 689. h. s. u. 



8. Prinzipien der Atomdynamik • von Dr. J. Stark. I Teil. 

 Die elekrischen Quanten. Pp. x, 124. Leipzig, 1910 (S. Hirzel). 

 — According to the author's preface, the present pamphlet is to 

 form the first part of a book which will consider especially the 



