8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



suggest that a constant value of wo.r may be approached equal to or 

 slightly greater than 67. On the basis of this value we may compute 

 a heat of dissociation corresponding to an absolute electron voltage 

 of 5.5 volts. This is in much better agreement with the value com- 



Table 2. — HCN Bands in I'apor 



Notation Abs. X v /}ii>,, I y(aver.) Ai' jIv., v v —v 



% y. cm.-' cm.-i 10*'"' cin.-' cm.-' cm.-' cm.-' cm.-i 



(4''i) 12636 12500 it 30 136 



2991 

 6.6 1. 0341 9670 ±3 



3"! 50 ±2 18 9645 133 9500 ± 10 145 

 6.5 1.0395 9620 ±3 



3124 

 80 1.5280 6544 ± 2 



2J'i 47 — 2 21 6521 107 6410 ±10 III 



75 1. 539 1 6497 ±2 



3231 



59 



8487 ± 10 104 



puted from chemical data, 4.2 volts, than would be obtained from 

 Badger's constant value of 43.7. 



The displacements to lower frequencies in passing from vapor to 

 liquid show a marked increase for the higher harmonics, with the 

 exception of the 4i'i value, for which it must be remembered that the 

 liquid value is only approximate. 



