pay ye? Report OF THE CHEMIST OF THE 
sulphide. The filtrate from the precipitates of lead sulphate 
and lead sulphide were united, concentrated to small volume 
on a water-bath, then made alkaline with barium carbonate and 
finally boiled about 15 minutes in order to remove all ammonia. 
The solution was then made slightly acid with sulphuric acid, 
the precipitated barium sulphate removed by filtration and the 
filtrate made to contain 5 per ct. acid by adding sulphuric acid, 
after which it was precipitated by phosphotungstic acid. A 
heavy crystalline precipitate resulted, which was filtered and 
washed with 200 cc. of 5 per ct. sulphuric acid. The phos- 
photungstic acid precipitate was then suspended in water and 
treated with barium hydroxide to remove the phosphotungstic 
acid in the well-known way. The excess of barium was removed 
by carbon dioxide, the precipitate filtered and washed. This 
gave a solution, which should contain the hexon bases, viz.: 
arginine, lysine, histidine and lysatine. For the separation of 
the first three compounds, the Kossel-Kutscher method was em- 
ployed, and, for lysatine, Siegfried’s method. To this solution, 
diluted to 2 liters and made slightly acid by sulphuric acid, was 
added a solution of silver nitrate, until a drop of the solution 
placed on a white porcelain surface gave with barium hydroxide 
the yellow precipitate of silver oxide, thus showing excess of 
silver nitrate. Then, barium hydroxide was added to satura- 
tion, which formed a somewhat slimy precipitate, filtering 
slowly. The precipitate was filtered and washed with saturated 
solution of barium hydroxide. The filtrate (Solution A) was 
worked for lysine, and the precipitate, for lysatine, histidine 
and arginine. The precipitate was suspended in warm water and 
the barium carefully removed by means of sulphuric acid and the 
silver by hydrogen sulphide. The precipitate was filtered, washed 
with water and the fillrate made to 1 liter (Solution B). 
In cheese 15 months old.— In 10 cc. of Solution B, the nitrogen 
was determined and found to be 0.00041 gram or a total of 0.041 
gram in the entire extract. This small amount of nitrogen indi- 
cates that arginine, histidine and lyastine were present in exceed- 
ingly minute quantities, if at all. Jt is possible that the small 
amount of nitrogen present was due to slight traces of peptones 
which tannin failed to remove. 
