10 Mr. W. Sutherland on the Fundamental 



with the solid element S to produce the solid compound RS 

 with evolution of heat g, then, to obtain the evolution of heat 

 when S as gas combines with R as gas to produce gaseous RS, 

 we must add the latent heat of vaporization of R and of S 

 and subtract that of RS: denoting these latent heats by L(R), 

 L(S), and L(RS), and the required heat of combination of 

 the gases by H(RS) we have 



H(RS) = ?-L(RS) + L(R) + L(S). . . (15) 



There remains now only to give tables of the experimental 

 data and the values of M 2 Z calculated from them by equations 

 (7)_, (11), and (13) , and of Mlp/J or L, the latent heat per 

 gramme-atom or gramme-molecule due to molecular force ; L 

 is given in kilocalories. As the application of (11) to the 

 metals brings out some immediately interesting results, the 

 values for the metals will be taken first. In the metals the 

 ordinary atomic mass (weight) is taken for M. 



Table I. 



First family and Copper sub-family. 



Li. Na. K Bb. Cs. Ou. Ag. Au. 



T 453 369 335 311 300 1330 1230 1310 



M/p 11-9 237 45-4 56*1 70-6 72 10-2 102 



M.H 4-1 8-6 16-2 21-2 276 111 159 187 



L(kcal.) 8-3 8*6 8-5 90 9-3 366 37-0 435 



Second family and Zinc sub-family. 



Be. Mg. Ca. Sr. Ba. Zn. Cd. Hg. 

 T 1230 1023 900 800 748 690 590 234 



M/p 5-6 138 25-4 34-9 365 91 12-9 14-7 



M.H 5-8 139 24-5 340 35-9 7'3 97 4-8 



L(kcal.) 24-5 239 23-0 23-2 23'4 191 179 7'8 



Third family and Gallium sub-family. 



Al. La. Ga. In. Tl. 



T 1123 710 303 449 563 



M/p 10-6 22-3 11-7 15-3 181 



MH 11-9 235 4-1 8-8 143 



L(kcal.) 268 25-2 8'4 136 18-8 



Fourth family and Tin sub-family. 



Ce. Sn. Pb. 



T 1000 503 599 



M/p 21-0 16-1 181 



M 2 2 279 109 15-3 



L(kcal.) 31*6 16'1 20\L 



