OP ARTS AND SCIENCES. 285 



I. 6298 grm. salt dried at 125° gave 0.4 11 G grm. PbSO,. 

 II. 0.G611 grm. salt dried at 125° gave 0.4G34 grm. PbSO^. 



Calculated for Found. 



PbCslIClSOo I. ir. 



Pb 47 97 47.88 47.88 



Potassic jB-Chlor-h-SuIphopyromucate, K^C^HCISO^ . IIjO 



The potassium salt was readily soluble even m cold water, but was 

 obtained by cooling a hot concentrated aqueous solution in the form 

 of transparent prisms, which effloresced over sulphuric acid. 



I. 0.7895 grm. air-dried salt gave 0.4260 grm. K^SO^. 

 II. 1.7840 grm. air-dried salt lost at 110° 0.1104 grm. HgO. 



Calculated for Found. 



KoCsHClSO,., . H.O I. II. 



K 24.39 24.22 



H2O 5.61 6.18 



I 0.9626 grm. salt dried at 110° gave 0.5464 grm. KoSO^. 

 II. 0.7043 grm. salt dried at 110° gave 0.4003 grm. KSO^. 



Calculated for Found. 



KaCsIlClSOe I. II 



K '25.83 25.48 25.52 



While there could be little doubt of the constitution of the sulpho- 

 nic acid formed from yS-chlorpyromucic acid, we attempted to establish 

 more definitely the position of its sulpho group by reducing it to the 

 8-sulphopyromucic acid, We found, however, that the chlorine was 

 much more firmly held than the bromine of the corresponding y8-brom- 

 8-sulphopyromucic acid, and that the reduction could not be effected by 

 the ordinary reducing agents. Zinc dust in an ammoniacal solution, 

 which had given satisfactory results with the bromsulphopyromucic 

 acids, removed the chlorine so slowly that, even after boiling the so- 

 lution for days, the reduction was far from complete. On the other 

 band, sodium amalgam added to the aqueous solution of the barium 

 salt at once attacked the sulpho group, baric sulphite was precipitated, 

 and /S-chlorpyromucic acid was formed. With other reducing agents 

 in acid solution we were equally unsuccessful. The ready elimination 

 of the sulpho group by the action of sodium amalgam in alkaline so- 

 lution was so unexpected that we were led to examine the behavior of 

 other sulphopyromucic acids under the same conditions. We found 

 that 8-sulphopyromucic acid was thus readily reduced to pyromucic 

 acid, while /3-sulphopyromucic acid was ajiparently unaffected, and that 



