18 



HYDRATES IN AQUEOUS SOLUTION. 



cases are well known, but there was found on record an unexpectedly large 

 number of salts that have already been shown to crystallize with varying 

 amounts of water, depending upon the temperature at which the crystals 

 were formed. A few examples are given to bring out the general relation, 

 that the number of molecules of water of crystallization is greater the lower 

 the temperature at which the salt is crystallized. 



