350 353 356 365 367 698° C. 

 623 626 629 638 640 \ 971°abs 



760 mm 

 /o^oriop = 0,778(-2) 0,991 ( -1) 0,164 0.425 0,470 0,517 0,565 0,602 0,628 0,660 0,741 0,788 [ 2,881 



As log'^'pic in atm. = 2,110 to 2,076, this is in mm. 4,991 to 

 4,957, and we find then : 



Here too the first row of values appears to be nearer the truth 

 tlian the second. As ƒ is still greatly increasing at Tg, the values 

 past 4,21 cannot possibly remain below the limiting value 4,25 (for 

 7^). This limiting value is namely y;^ = 8y = 10,19 to 9,79, i.e. 

 /V° = 4,48 to 4,25. Perhaps Tu lies slightly below 1660° abs. 



6. Caesium. At last the last member of the group. Here the 

 triple point is at 28°, 25 C. = 301°, 3 abs.; the boiling point is at 

 670° C. (RuFP and Joh.j = 943°,1 abs. So that 7\. will lie between 

 301,3 X 5\/, = 1607, 943,1 X 1,7 = 1B03, mean 1605 ° abs., and 



301,3 X 47, = 1406, 943,1 X 1,5 =1415, averaged and rounded off 

 1410° abs. 



We find therefore 40,06 to 37,55 for 7 A;, yielding 2y = 2,522 

 lu 2,427, 7 = 1,26 to 1,21. The value of y : (1 + y) becomes 

 0,558 to 0,548, so that X becomes = 0,924 to 0,931, and (f = 1^,11 

 to 75,36. And we find for b],-. 



2,522 X 132,81 334,9 



bk — = ~ = 725 . 10 -5i 



2,061X22412 46 90 \ 



2,427 X 132,81 322,8 



or bk = — = — = 688 . 10-5 



2,090 X 22412 46840 



because D^ =: 2,061 to 2,090. For the density at the melting-point 

 28°, 25 Hackspili, gives namely />=: 1,845, so that 



