TRIMETHYLAMINE IN AUSTRALIAN SALT BUSH. 241 



clear supernatant liquid siphoned off from the precipitate, 

 the residue being washed twice with water. On removing 

 the excess of lead from the filtrate by means of hydrogen 

 sulphide a considerable amount of sulphur separated out on 

 standing, this being probably due to *the action of the 

 nitrates in the plant upon the hydrogen sulphide. A 

 quantity of potassium nitrate also crystallised out when 

 the lead free filtrate was evaporated to dryness. The dry 

 residue was then extracted with alcohol and the clear 

 alcoholic solution treated with an alcoholic solution of 

 mercuric chloride and allowed to stand four days, the clear 

 supernatant liquid was siphoned off and the precipitated 

 double salt of the bases washed five or six times with 

 alcohol and warmed with E strength hydrochloric acid till 

 no more would dissolve. A brown insoluble residue was 

 filtered off and the filtrate evaporated, under diminished 

 pressure, to dryness. This dry residue was again extracted 

 with absolute alcohol, the filtrate again evaporated as 

 before, and the process repeated till no more potassium 

 chloride could be thus separated. The last alcoholic solu- 

 tion on diluting with water gave a dark precipitate which 

 became crystalline on standing, this was filtered off, washed 

 and put by for subsequent examination. 



Mercury was removed from the aqueous filtrate by means 

 of hydrogen sulphide and the mercury free filtrate evapor- 

 ated under diminished pressure, the dry residue extracted 

 with absolute alcohol, filtered, and the process repeated 

 till only a small amount of potassium could be detected in 

 the dry residue. The alcoholic solution of this residue was 

 precipitated with alcoholic platinum chloride and the buff- 

 coloured precipitate filtered and washed with alcohol till 

 free from excess of platinum chloride and dried. On crys- 

 tallising this double platinum salt from water over sulphuric 

 acid in a vacuum desiccator orange-red dodecahedrons and 

 hexagonal plates separated out. 



P— December 3,|1913. 



