366 IRON, NICKEL, COBALT, C . 



altered in its appearance, and rendered inso- 

 luble. 



Five atoms of water weigh 5 '625, which weight 

 exceeds 5-48 by only 0*145, or about the eighth 

 part of an atom fc There is no reason to doubt 

 that the aqueous portion of this salt constitutes 

 a determinate number of atoms; and since 

 15*125 of the salt contain exactly one atom of sul- 

 phuric acid, the atomic weight of the water 

 must exist also in the same quantity. Now, the 

 results just stated point out unequivocally that 

 five atoms of water are united in it with an inte- 

 grant particle of anhydrous protosulphate. Thus 

 it appears, that 15*125 grains of protosulphate 

 of manganese contain 5*625 grains of water. 



3. The five grains of sulphuric acid and the 

 5*625 grains of water make together 10*625 

 grains. This quantity, subtracted from the ori- 

 ginal weight, leaves 4*5, which must denote the 

 quantity of protoxide of manganese present. 

 Thus it appears, that protosulphate of manganese 

 is composed of 



Sulphuric acid 5 



Protoxide of manganese 4*5 

 Water . . . 5-625, 



15-125 



Atom of ^ S ^ e sa ^ * s neutra ^ an ^ as 5 is the weight of 

 protoxide an atom of sulphuric acid, 4*5 must be the 



of manga- . . * . 



nese. atomic weight of protoxide or manganese. 



