14 
278,1 178,5 
ia” 30% 
hence pp == 79,4 atm. (PermaroN found 76,1). 
With 7;,=141°,0 C. according to Dewar log p; would have 
been 0,5610 « 0,6595 5,087 = 1,882, hence p, = 76,3. (Dewar 
found 83,9). 
As f at — 34°,5 is somewhat greater than at 0° C., p, must be 
< 79,4 (resp. 76,3). The value 76,1 found by PrrraroN can thus 
be exact, that of Dewar is probably too high. 
If we calculate the values of a, and bj for Cl, found by us in 
I with the values found by Perraron for 7}, and pj, viz. 417,1 abs. 
and 76,l atm., we find the somewhat higher values bj. == 251 « 107, 
Var 14,5 X 10-2, instead of bj. = 226 < 105, War= 10,9 XxX 10-2; 
giving for Cl the values resp. 125 and 5,75. (From the compounds 
we found 115 and 5,4). 
For mercury at 500° C. p= 5435,0 mm. = 7,151 atm. Further 
T= oot U. bal: abs. Tr = 1700 abs. Bence: 
log pr. = 90,8544 X iad NK. Une 
; “* 1260 143 
giving pr — 204, while we have found 192 by another way. 
The value of / being somewhat greater also here at 357° than 
at 500°, p, must in any case be < 204, so that 192 may be correct. 
When the case presents itself that both 7% and pj are unknown, 
it is yet possible to caleulate both values — at least with some 
approximation. From log pie log p= f(Tkj,—1) we have then 
log pr — log 3.6395 X 
= "5610 0,6547 «5,174 = 1,900, 
= 0,8544 2,703 = 2,309, 
namely : 
Ty, 
“i 
If we now put f+ log pr=y. f Tr=x, then 
fF log pk = log p vag 
x 
y log pT ME ee soley ie het OER 
so that we can calculate the quantities 7 and y from two corre- 
sponding pairs of values. Then we have, however, only f + log px 
and 7; (again on the supposition that the value of f does not 
appreciably differ for one pair from that of the other pair). To 
eliminate further the value of f, we may make use of the found 
property of the quantities “a, that they will namely be about 
constant in a whole horizontal principal series of the periodic 
system, e.g.=9 in the series of I and Sb,—7 in the series of 
Be and As, ete. 
