106 



Mr. E. Scliuiick on the Colouring and 



[Recess^ 



that adopted in preparing for Analysis VIII. of Series A. It was also ana- 

 lyzed, but the results present nothing of interest. 



D (1857). 



The lead compounds next analyzed were procured from the same source 

 as those of Series A. Urine was mixed with a solution of acetate of lead 

 as long as a precipitate was produced, and to the filtered liquid basic ace- 

 tate of lead was added, w^hich gave, as usual, an abundant precipitate. 

 This was allowed to settle, washed, filtered off, and then treated with cold 

 dilate sulphuric acid. The excess of the latter having been removed by 

 means of carbonate of lead, the filtered liquid was evaporated in the usual 

 manner by means of a current of air. The syrup which was left behind 

 was dissolved in a little water, and the solution was mixed with a large 

 quantity of alcohol. To the filtered liquid there was added an alcoholic 

 solution of acetate of lead and some ammonia. The precipitate thereby 

 produced was filtered off, washed with alcohol, and then treated with dilute 

 sulphuric acid. The excess of acid having been removed with carbonate 

 of lead, the filtered liquid was evaporated in the usual manner to a syrup. 

 This syrap was poured into a flask together with a little alcohol, and a large 

 quantity of ether was then added, which caused the separation of a glutinous 

 substance that was slowly deposited at the bottom of the vessel. After 

 the ethereal solution had become clear, it was poured off from the glutinous 

 deposit {d) and evaporated, and the residue was treated with water, which 

 left a little fatty matter undissolved. The filtered liquid was evaporated 

 in the usual manner to a syrup, which was dissolved in alcohol. On the 

 addition of acetate of lead and a little ammonia to this solution, a cream- 

 coloured precipitate fell, which was filtered off, washed with alcohol, dried 

 r/^ vacuo, and analyzed. It contained no trace of chloride of lead. 



I. 0'9905 grm. gave 0'7145 grm. carbonic acid and 0*2030 grm. water. 

 1*2625 grm. gave 0*1285 grm. chloride of platinum and ammonium. 

 0*6400 grm. gave 0*5265 grm. sulphate of lead. 

 These numbers correspond, in 100 parts, to 



G 19*67 



H 2*27 



N 0*63 



16*90 



PbO 60*53 



100-00 



The substance combined with oxide of lead contained, in 100 parts, 



49-83 



il 5*75 



N 1-62 



O 42*80 



100*00 



It will be seen that the composition of the substance combined with oxide 



