us ivAnganese. 



It forms two oxides, the black and the grey. 



Nickel alloys with most of the metals, and it is 

 found alloyed with iron in those masses that fall 

 from the atmosphere, called meteoric stones. The 

 origin of those lapideous masses that appear in so 

 extraordinary a manner is entirely unknown: but 

 the numerous well-authenticated accounts we have 

 had of the fact put it now beyond dispute. They 

 are first seen as large meteors, at a great height in 

 the air, which suddenly burst with an explosion, 

 and the fragments are seen to fall to the earth. It 

 is very remarkable that their composition is always 

 the same, although they have fallen at many difter- 

 ent times, ,and in different places. They always 

 contain native iron alloyed with nickel, in grains 

 imbedded in a stony matter. The substance of 

 these meteoric stones is not like any bodies which 

 are found in the earth. In 1795, one weighing 

 56 lbs. fell in Yorkshire. 



MANGANESE. 



This metal is never found native. Indeed its 

 attraction for oxygen is so powerful, that it is with 

 difficulty preserved in the metalHc state. When 

 pure, it is of a greyish colour, much like cast iron, 

 and not malleable. It soon tarnishes, and at last 

 becomes black. This change takes place more 

 rapidly, if the metal be heated, or put into water. 



There appear to be two oxides of this metal ; the 

 protoxide^ which is of a greenish colour ; and the 

 peroxide, which is steel black, and has a consi- 

 derable lustre: the latter is found in abundance, 

 particularly near Exeter, and is much used in 

 bleaching, and also for procuring oxygen gas, as 

 it parts with it simply by the application of heat. It 



