and Saline Solutions at High Temperatures. 



87 



ing formula, whicli gives the results shown below, and corre- 

 sponds sufficiently well with that deduced from Kopp's experi- 

 ments, to prove that the expansion follows much the same law, 

 both above and below 100° C. : — 



V= -9977 -J- -000123^ + -OOOOOSSOi^. 



Not taking into consideration the volume at 0°, these calculated 

 numbers agree with the experiments as well as could be expected, 

 except at 200°, which is a determination far more open to doubt 

 than any of the others ; and I therefore think that we may con- 

 clude provisionally, that the formula would enable us to deter- 

 mine with approximate accuracy the volume of water at still 

 higher temperatures, whilst at the same time we must always 

 consider it probable that this calculated volume would be less 

 than the truth. Thus, for instance, it indicates that at 300° C. 

 water would occupy at least f of its bulk at the ordinary tem- 

 perature of the atmosphere. 



Having found it requisite to ascertain what influence the pre- 

 sence of various salts exercises on the expansion of water, I made 

 a number of experiments, which lead to some curious results. 

 In the case of chloride of potassium dissolved in three times its 

 weight of water, I found the volumes to be as under : — 



Though the amount of the expansion varies very considerably, 

 the general facts arc much the same as in the case of water. The 



