480 Wells — Alleged Variable Composition of 



constant proportion, containing less cesium and more gold 

 than the dark red double salt Cs 5 Au 3 Cl 14 . The sparingly 

 soluble, yellow double salt CsAuCl 4 , into which the red one 

 is instantly converted by the action of water, with the loss 

 of cesium chloride by its going into solution, fulfills the 

 requirement in its composition. It is easy to explain 

 the presence of moderate and fairly constant amounts 

 of this yellow salt in Bayer's products in connection with 

 his method of removing mother-liquor from his crops of 

 crystals by suction, presumably with moist air, for I 

 have found that when some of the minute, brilliant 

 crystals of the red salt were placed upon a perfectly 

 clean, dry watch-glass in a closed vessel containing air in 

 contact with water, for a few hours at room temperature, 

 the crystals were changed to droplets of liquid containing 

 clusters of minute crystals of the yellow salt. 



The deliquescent character and consequent decom- 

 position of the red double salt, therefore, explains 

 perfectly the presence of the yellow compound in all of 

 Bayer's analyzed products. The proportion of this 

 salt necessary to bring the calculations into perfectly 

 satisfactory agreement with the analyses is from about 

 2% to about 10% of the whole mixture. One per cent 

 of it in the place of the same amount of the red salt 

 increases the gold to the extent of 0.08% and decreases 

 the cesium about 0.10%. Two calculations are given 

 below where the presence of 5 and 10% of the yellow 

 salt is assumed : 



Cs Ag Au CI 



Calculated for Cs 9 AgAuCl 6 (A) 33.90 13.77 25.17 27.16 



Calculated for Cs 5 Aii 3 Cl 14 (B) 37.90 .... 33.77 28.33 



Calculated for CsAuCl 4 (C) 28.15 .... 41.79 30.06 



One of Bayer's analyses, - 34.8 8.50 29.0 27.8 



Calculated for 0.617A4-0.383B, 35.43 8.50 28.46 27.61 

 Calc. for 0.617A+0.333B+0.05C, 34.94 8.50 28.86 27.70 



Another analysis by Bayer, 35.0 7.47 29.6 27.85 



Calculated for 0.54A+0.46B, 35.74 7.44 29.13 27.70 



Calc. for 0.54A+0.36B+0.10C, 34.76 7.44 29.93 27.87 



In the first of these two calculations very close agree- 

 ments with the analysis are obtained by assuming 5% 



