ANTIMONY. 197 



These results, confirmatory of the work of Schneider, 

 were presented to the American Academy in 1876. Still, 

 before publication, Cooke thought it best to repeat the work 

 of Dumas, in order to detect the cause of the old discrepancy 

 between the values Sb = 120 and Sb = 122. Accordingly, 

 various samples of antimony trichloride were taken, and 

 purified b}^ repeated distillations. The final distillate was 

 further subjected to several recrystallizations from the fused 

 state; or, in one case, from a saturated solution in bisulphide 

 of carbon. The portions analyzed were dissolved in con- 

 centrated aqueous tartaric acid, and precipitated by silver 

 nitrate, many precautions being observed. The silver chlo- 

 ride was collected by reverse filtration, and dried at temper- 

 atures from 110° to 120°. In one experiment the antimony 

 was first removed by H2S. Seventeen experiments were 

 made, giving, if Ag = 108 and CI =: 35.5, a mean value of 

 Sb = 121.94. If we reduce to a common standard, Cooke's 

 analyses give, as proportional to 100 parts of AgCl, the 

 Cjuantities of SbCl^j stated in the third column: 



1-5974 gnu. SbCla gave 3.0124 grm. AgCl. 53-028 



.0096 



This mean may be combined with that of Kessler's series, 

 as follows : 



