4 Art. 2.— T. Suzuki: The Change of 



from which it will be seen that twu cobalt atoms, in becoming 

 cobaltic, pair together and lose only one nitroxyl group, the third 

 cobalt atom remaining cobaltous, though also losing a nitroxyl 

 group. The equation of the actual change is 



6 Co"(NOo), + 2H,,0 = Co",Co",,(NO,)io(OH), + 2NO, 



in which 



Co",Co'"2(NO.)io(OH),=3Co"(NO.).,Co'".(NO,)3(OH)3,Co"(N02)(OH). 



That is, six molecules of cobalt nitrite become united, half of 

 them unaltered and the other three, with loss of 2N0 and acquisi- 

 tion of 2H2O, as cobaltic and cobaltous hemihydroxy-nitrites. 

 This condensation of the six molecules into a complex happens 

 without any union taking place of the atoms of cobalt with each 

 other through the agency of their ordinary valencies, which are, 

 it will be seen, used up in the union of tlie cobalt with nitroxyl 

 and hydroxyl atoms. 



The change just formulated must be treated as indivisible, but 

 other changes occur which may be regarded as secondary to it. 

 There is evidently a cumulative resolution of the molecules of the 

 Co"4Co"'2(N02)io(OH)4 into others simpler by having given up some or 

 all of their cobaltous hydroxynitrite and others enriched by having 

 received this additional cobaltous hydroxynitrite. This resolu- 

 tion is attended with another one, that of some of the cobaltous 

 hydroxynitrite into nitrite and hydroxide, the latter retained by the 

 hydroxycobaltinitrite, the former lost to it by undergoing conver- 

 sion itself to cobaltinitrite in a way similar to the original change. 

 These subsidiary changes may be attributed in part to the force 

 of crystallisation, but are principally to be referred to the feeble 

 hold of the cobaltinitrite upon much cobaltous hydroxynitrite 

 against the tendency of this to become itself cobaltic. The last 



