206 THE EARL OF BERKELEY ON SOME 



Column III. gives the corresponding solubilities in parts of anhydrous salt 

 dissolved by 1 00 parts of water, and is also a summary of some 450 

 observations exclusive of the above mentioned 300. 



Column IV. gives the number of gram-molecules of salt in i litre of solution 

 saturated at the temperature recorded in column I. The numbers are 

 obtained by dividing the weight of salt found in the litre by the molecular 

 weight of that salt. 



Column V. gives the number of gram-molecules of water in the litre. The 

 numbers are derived by dividing the weight of the water in 1 litre of 

 saturated solution by the molecular weight of water. Throughout this 

 work the atomic weights used are those based on hydrogen as unity and 

 oxygen as equal to I5 - 88. 



Column VI. gives a measure of the concentration it is the ratio of the 

 number of salt molecules to the sum of salt and water molecules in the 

 same volume of solution. 



Column VII. gives the solubilities, taken from COMEY'S ' Dictionary of 

 Solubilities,' of such salts as have already been investigated. 



SODIUM Chloride. 



The solubilities were determined by evaporating to dryness in Jena glass bulbs. 



1 The numbers in this column are the densities of the saturated solution of NALL obtained by ANDRIA 

 (' J. Prakt. Chem.,' [2], 30, 305), and reduced to the temperatures given in column I. 



