( 393 ) 



has aiiotlier giuuiid. Mr. Veksciiaffelt himself rcmarkts, that if he 

 liad niaflo use of other experimental data to determine the values 

 of «, h and c, he would have found the following formula: 



y — 0,9995 + 0,00130 (1—,') + 0,005G (1— .t)2 . 



But he uses the former — and now I shall show that the latter 

 agrees to a great extent with what his own experiments teach, and 

 tliat the former certainly cannot be true. 



When two gases are mixed in different proportions — and one 

 of the gases (carbonic acid) deviates in one direction from the law 

 of Boyle, whereas the other gas (hydrogen) does so in the other 

 direction, we may expect the existence of a mixture, which follows 

 the law of Boyle. What may be brought about by change of tempe- 

 rature in case of a simple gas, occurs here by change of the mixing 

 proportion. For such a mixture i/ = !• From the formula 



1 =0,99031 + 0,006(1— j-)^ 



follows .(• = ± -/y. From the formula 



1 = 0,9995 + 0,00130 (1— .i) -f 0,005(3 (1— ic)-j 



follows .(■ = 0,8. 



Mr. Yekschaffelt has made observations for ;(• = 0,7963 and 

 X = 0,6445. The products jiv for x = 0,7963 are respectively 



1,0740, 1,0750, 1,0704, 1,0749, 1,0748. 



At y = 0,02 pv has still the value of 1,0750, and not before 

 V — 0,01 it has reached the value of 1,0960. 



From these values of pv we may conclude that the mixture has 

 nearly that composition, in which it would follow the law of Boyle 

 in great volumes. From the long series of larger volumes, in which 

 actually constancy of this product has been found, we might deduce, 

 that the mixture deviates still in the direction of carbonic acid — 

 and that therefore x should have a somewhat greater value in order 

 to form a mixture, which follows the law of Boyle only in verv 

 large volumes, but yet shows an increasing product from the be- 

 ginning. 



If we take the value of pv that belongs to the mixture, in which 

 .(• = 0,6445, we find : 



1,0431, 1,0425, 1,0413, 1,0411, 1,0413, 1,041, 



27 



Troceediugs Royal Acad. Amsterdam. Vol. I. 



