PLATINUM. SEUBERT. 



The proper names are potassium chloro-platinate, 

 ammonium bromo-platinate, etc. We must be permitted to 

 use these names in this section. 



The only additional chemical fact which it is important 

 to bear in mind is the ready and complete decomposition of 

 these compounds by ignition, leaving always the platinum in 

 the metallic state, the potassium as water-soluble chloride, 

 while ammonium and similar radicals are completely 

 volatilized. 



It is this ready dry way decomposition leaving the pro- 

 duct in a most admirable condition for exact weighing, 

 ready production of the substance in a chemically pure 

 crystal form, which first attracted the special attention of 

 Berzelius to the simpler members of this group of salts for 

 atomic weight determinations. 



We shall now give the experimental data in our usual 

 form. 



Pt : Am2 Cle Pt = 195 : 444=10.43 919. Change 13 high. 



Scubertj iSSi : 



Series I, Det. 6, Extr. 963 946; 17. Mean 37 high. 



" II, Det. 6, " 889 871518. " 43 low. 



" III, Det. 9, " 026 986; 40. " 82 high. 



Mean of all, 21 Det. " 34 high. 



" " Series I, II, 12 Det. " 3 low. 



Halberstadt, 1884: 



Reduction, Det. 10, Extr. on 880; 131. Mean 32 high. 



Electrolysis, Det. 8, " 979 894; 85. " 15 high. 



Mean of all, 18 Det. " 24 high. 



Pt : Ka2 Cl Pt= 195 : 486 = 0.40 124. Change 12 high. 



Seubert, 1881 : 



4 7 *> Det - S, Extr. 130 0705 60. Mean 17 low. 

 Halberstadt, 1884: 



Reduction, Det. 8, Extr. 127 069; 58. 

 Electrolysis, Det. u, u 126 0635 63. 



All 19 Det., 127 063; 64. Mean 26 low. 

 Pt : Arm Brc Pt = 195 : 711 =0.27 426. Change 10 high. 



