2 
Physics. — “On the Fundamental Values of the Quantities b and 
Va for Different Elements, in Connection with the Periodic 
System IL. Mercury and Antimonium. General Methods’. By 
Dr. J. J. van Laar. (Communicated by Prof. H. A. Lorentz). 
(Communicated in the meeting of March 25, 1916). 
I. In our foregoing paper *) we have found that the values of 5 
and p/a at the critical temperature can be built up additively from 
a few constant fundamental values for the different elements. (See 
the tables on p.1223 and p.1229 of the cited paper). The elements 
H, C, N, and O presented in this, as far as the values of 4 are 
concerned, two different fundamental values (H even three), of which 
the second may be considered as a contraction — about in the 
ratio of /,M2:1 — of the fundamental value. [For H the third 
value is to the first as (l—'/,V2):1]. The way in which these 
multiple values must be used in the reconstruction of the values of 
hb and Va of the different chemical combinations has been sufficiently 
set forth in the first paper (henceforth to be indicated by lL). (See the 
different tables and the summary on p. 1234). With regard to the 
values of Wa we should pay attention to the fact that for compounds 
as CH,, CCl,, CH,Cl CHC), C,H, ete. and also for NH, and PER 
GeCl, and SnCl,, the central atoms do not take part in the attrac- 
tion; so that in the reconstruction the values of a for C,N, P, 
Ge, Sn must all be put =O. But for doubly bound C half the value 
C=1,55 is found, and for the triply bound C the full value 3,1. 
(see further again the tables, and also p. 1220—1221 and 1235; 
also with regard to the two values for H). 
Below we reproduce the two principal tables *). 
Fundamental Values for by, > 105. 
| | He = 105? 
H=485 | Cc =100 | N =e | 0 =® | F =m || Nea WP 
(34,14) | (75) (60) (50) 
Si=155) |P =o} 5 +125 | Oi Ar = 144 
Ge= 210 | {As = 195) | Se. = 130 | 
Sn =265  Sb—250_ (Te = 235) | 1 =220 || X = 228 
1) These Proc. of Jan. 29, 1916. 
2) In the table for Va on p. 1229 Ne = 6,3 X 10 ?[=V(39,6 X 10—2)] has 
been written instead of Ne=2,0 X10 ?[=V (38,96 X 10 *]. Correct further on 
p. 1224:H, found = 97° instead of 97; on p. 1229: Hy found = 1,96 instead of 
1,95; on p 1237 read: neutralized in ordinary circumstances ; “closed”, as M. 
expresses himself — would be free and “open”’. 
