For nitrogen we found -. 



For argon : 



and hence for the triple point 7"= 83°, 81 yy = 521,4 in.m. 



We siiall compare these tigiires with some recent ones of otlier 

 observers. 



For oxygen the measurements by Henning ') and by v. Siemens^) 

 may be used. 



For all these raeasnrements we have drawn /w/. y^ = ƒ I — ]. The 



1) F. Henning. Ann. d. Phys. (43) 282, 1914. 



-) H V. Siemens. Ann. d. Phys. (42) 882, 1913. Comp. also G. Holst. Comm. 

 Leiden N«. 148a. 



