24 



PROCEEDINGS OF THE AMERICAN ACADEMY 



pliurous oxide is given off, but it is only by strong heating that the 

 whole of the oxide can be expelled. Of this salt : — 



0-7132 gr. gave 0-3800 gr. SO^Co = 20-27% cobalt. 

 1-7094 gr. gave 2-0505 gr. SO,Ba= 32-94'-X, SO^. 

 1-5422 gr. gave 0-9228 gr. water = 6-64% hydrogen. 

 0-8927 gr. gave 183 c.c. nitrogen at IS'^-S C. and 765-14'"" = 

 24-07%. 



The formula Co, {^11,) ^^{SO.,)^ + SOU, requires : — 



Calculated. Found. 



2 20-27 20-27 



3 32-98 32-94 

 10 24-05 24-07 

 36 6-18 6-64 



I have assigned this salt somewhat arbitrarily to the roseocobalt series. 

 In the absence of any direct evidence on either side, it is of course 

 equally probable that it belongs to the series of purpureocobalt. 

 Kiiuzel's salt, 



Co,(NH3),„(S03)3+Co,(SO,)3+90H„ 



bears the same relation to the neutral sulphite which I have de- 

 scribed which the cobalto-nitrite, Co,(NH3)j„(NOJg-|~C'^2(-^^:i)6' 

 bears to the normal nitrite Co2(NH3)j(,(NO,),;. 



The salts known witli most certainty to belong to the roseocobalt 

 series are the following : — 



Cobalt, 



Sulpliurous Oxide, 

 Kitrogen, 

 Hydrogen, 



Chloride, 



Nitrate, 



Suli)hatcs a, ^, y, 



Acid su]|)hate, 



lodo-sulphates a, ^, y* 



liromo-sulphate,* 



Dichromate, 



Basic oxalo-sulphate. 



Oxalate, 



Acid oxalo-bisulphate, 



Acid oxalate, 

 Ferricyanide, 



Co,(NH,),„Cl,+20H., 



Co,(NH3),„(NO,)„+20H, 



Co,(NH3),„(SO,)3+50H, 



Co,(NIl3),„(SOj.,+SO,H,+40H2 



Co,(NH3),„(SOJ,l,+201I, 



Co,(NIl3),„(SO,),Br,+20a. 



Co,(NH3),„(Cr,0,)3+50H, 



Co,(NH3),,.O.(a0,)(S0,)+70H, 



Co,(NH,),n(C.,0,)3+60H.. 



Co,(Nii.),„(CA)(soj,+an30,+ 



2011., 



Co,(NIl3),o(aO,),-,+4C,IIA 

 Co,(NIl3)„Cy„+Fe,Cy„+30H, 



* Ivrok, loc. cit. 



