the Transparent Liquids by Increase of Temperature. 349 



and taking the averages of four such sets of values, I obtained 

 as follows : — 



a = -592869, 



b =288-5649, 



c 2 =117-7508. 



Further research might have yielded values giving results in 

 the calculation of the volumes nearer, on the whole, to the 

 observed volumes than these do ; but it appeared unnecessary, 

 since it is admitted that the apparent volumes need small but 

 unascertained corrections, and some small allowance is needed 

 for unavoidable error of experiment. 



The results of M. Drion^s observations* are placed in the first 

 two columns of the Table annexed, and the volumes calculated 

 by the hyperbolic formula in the third column : — 



Temperature by 

 Centigrade- 



Apparent 

 volumes of 



The volumes 

 calculated by 



Differences. 



thermometer. 



hydrochloric 

 ether observed. 



the formula. 





o 



0- 



100000 



1-00000 



•00000 



126 



1-01952 



101956 



+ -00004 



26-4 



104285 



1-04202 



-•00083 



350 



105856 



105725 



-•00131 



45-5 



1-07867 



1-07731 



-•00136 



590 



1-10670 



110580 



-•00090 



71-5 



1-13536 



1-13534 



-•00002 



830 



116470 



116568 



+ -00098 



93-5 



1-19460 



119652 



+•00192 



1030 



1-22479 



1-22742 



+ -00263 



1120 



1-25669 



1-25977 



+ -00308 



120-5 



1-29079 



1-29350 



+ -00271 



1280 



1-32489 



132622 



+ -00133 



1330 



1-35073 



1-34979 



-•00094 



The differences at the utmost are only small numbers, com- 

 mencing in the third place of decimals ; and I think we are 

 entitled to conclude that hydrochloric ether, one of the very 

 expansible liquids, has its volume a hyperbolic function of the 

 temperature, and the general physical properties are connected 

 by three constant magnitudes. 



M. Drion shows that the expansion is equal to that of air 

 at about the temperature 110° C. ; at 130° C. it is nearly 3 \ times 

 as expansible as at the freezing-point, and it becomes entirely 

 vapour at about 170° C. 



In M. Drion 5 s experiments with the liquid nitrous acid (acide 



hypazotique), they could be carried only from 0° C. to about 



90 C, on account of the termination of the liquid in the stem 



* Annalesde Chimieet de Physique for May 1859, 



