50 Professsor How on the Hyposulphites 



opaque white tufts of needles, which are rendered pure by 

 one crystallization from water. It is perfectly neutral to 

 test paper, dissolves readily in boiling water, and is imme- 

 diately deposited on cooling, as it requires about 300 parts 

 of this menstruum at the ordinary temperature, to retain it in 

 solution. 



It is readily obtained by double decomposition between hy- 

 posulphite of soda and hot solution of neutral salts ; but if the 

 former reagent be added to a cold solution of the crystallized 

 acid sulphate of quinine, the fluid becomes instantly milky, 

 from the presence of precipitated sulphur, and smells of sul- 

 phurous acid ; and when it has become clear, the walls of the 

 vessel are seen to be covered with the peculiar dendritic crys- 

 tals of the hyposulphite of quinine. 



When dried, it afforded these results on analysis : — 



3-883 grains, dried at 212°, gave 

 8'945 ... carbonic acid, and 

 2-365 ... water. 



3*435 ... dried, gave by deflagration, 

 2*080 ... sulphate of baryta. 





Experiment. 



. 62-82 

 6-76 



8-30 



Calculation. 





Carbon, . 

 Hydrogen, 

 Nitrogen, 

 Oxygen, 

 Sulphur, 



62-99 C 40 

 656 H 25 

 7-34 N 2 



14-72 7 

 8-39 S a 



240 

 25 

 28 

 56 

 [32 



100-00 100-00 381 



which agree perfectly with the formula for the dry salt, 



C 40 H^ N 2 O t , HO S 2 2 



The crystals contain in addition two equivalents of water, 



J 3-640 grains, air-dry, lost at 212° 

 (0-170 ... water. 



leading to a percentage of 4-67, and 4-51 is required by theory 

 for the formula 



C 40 H 24 N 2 O 4 ,HO,S 2 O 2 + 2aq. 



The mean results of the analyses of this substance by We- 

 therill,* to which I have already alluded, were these : — 



* Liebig's Annalen, lxvi., page 150. 



