Ill 



line discussed just now this valne is slightly too low ; this proves 

 that the vapour was no longer perfectly saturate with respect to the 

 white liquid phosphorus, which we think by no means astonishhig. 

 By means of the linear relation (9) the constant 6' may now again 

 be easily found in the following way from the value which tiie first 

 member possesses at two different temperatures. 



2\ Inp^ + 3.59 7', In 7', = - ^ + C' T, . . . . (lU) 



Qo 



1\ Inp, + 3.59 U\ In 7\ = - -^ + C 7\ . . . . (11) 



from which follows that : 



(7> y, + 3.59r>r,)-(T>p, + 3.59r,z»r.) 



C= T —T ~ ■""• ■ ^ ^ 



In this way we find C = 37.62. 



If we substitute this value in (9), we get : 



Tlnp + 3.59 T In 7' = — — ° + 37.62 T . . . . (13) 



3. Cnlculnt/'oii of Q^ mid of tlw. vapour tension. 



By means of this relation we can now calculate the value of — 



R 

 from the different observations. 



The result of this calculation is recorded in the following table, 

 (see p. 112). 



In the fifth column the found values for — are given, which give 



R 



as mean the value 8257, from which follows that Q„ = 16,35 kgs. cal. 

 The sixth column gives the discrepancies which the different results 

 present from the mean, and it appears from this that they are com- 

 paratively small, and now exhibit the positive sign, now the nega- 

 tive sign. 



Qo 



If this value for —- is substituted in equation (13), we get: 

 R 



Tlnp 4- 3.59 77/, 7' = 37.62 T — 8257 .... (14) 



by the aid of which we can now calculate the pressures for the 



different observation temperatures. 



We find the result of this calculalion in column 7. 



These calculated pressures harmonize on the whole as well with 

 the observed ones, as can be desired under the given circnmstances. 

 This is shown most convincingly by the last column, which gives 

 the difTerence between the calculated and the observed pressure. It 

 is evident that this difference should not be considered in itself, but 



