CHAP. X. 



OF THE ATOMIC WEIGHTS OF IRON, NICKEL, 

 COBALT, MANGANESE, AND CERIUM. 



THESE metals are very nearly related to each 

 other, both in their atomic weights and in the 

 proportions of oxygen with which they combine. 

 Each of them forms at least two oxides, the 

 first containing an atom of oxygen, and the 

 second an atom and a half of oxygen united to 

 an atom of the metal; and both of these oxides, 

 at least in the case of iron and manganese, is 

 capable of combining with acids. One of these 

 metals, I mean manganese, unites with two, if 

 not three, additional dozes of oxygen, forming 

 an oxide neither possessing alkaline nor acid 

 properties, and one or two oxides capable of 

 combining with bases, and consequently, pos- 

 sessing the characters of acids. 



SECT. I. 



OF THE ATOMIC WEIGHT OF IRON. 



Analysis of 



PROTOSULPHATE of iron, or green vitriol, is aprotosui. 



phate of 



salt which has been long known, and manutac- iron. 



Y4 



