New YorK AGRICULTURAL EXPERIMENT STATION. 225 
LYSINE. 
Solution A, obtained as described on p. 222, was freed from 
barium by sulphuric acid and from silver by hydrogen ‘sulphide, 
and the filtrate from these precipitates concentrated to small 
volume. The solution was made to contain 5 per ct. of sulphuric 
acid and precipitated with phosphotungstic acid. The precipitate 
was filtered, washed with dilute sulphuric acid, suspended in 
water, decomposed by barium hydroxide, filtered, and the excess 
of barium removed by carbon dioxide, the solution then being 
concentrated to small volume. 
In cheese 15 months old.— To the solution thus concentrated, 
alcohol of 95 per ct. strength was added in quantity equal to 
twice the bulk of the solution. Picric acid was then added. On 
standing 24 hours, no precipitate appeared. The alcohol was 
then evaporated, the solution concentrated and saturated picric 
acid solution added, when crystals began to appear and increased 
considerably on standing over night. The crystals were filtered, 
washed with cold water, recrystalized four times from water, 
finally washed with ether and dried over sulphuric acid, yielding 
9.2 grams (Fraction No. 1). 
The filtrate from the first fraction of crystals was further con- 
centrated by evaporation and more picric acid was added, pro- 
ducing a small additional yield of crystals. These were filtered, 
washed with ether and alcohol and dried over sulphuric acid, 
yielding 0.8 gram (Fraction No. 2). 
The last filtrate was further concentrated by evaporation, 
when a slimy precipitate separated. The whole mixture was then 
shaken with ether in sulphuric acid solution in order to remove 
all picrie acid, after which it was repeatedly boiled with animal 
charcoal and filtered to remove all coloring matter. The solu- 
tion was then reprecipitated by phosphotungstic acid, the pre- 
cipitate decomposed by barium hydroxide, filtered, and excess of 
barium removed by carbon dioxide, the resulting solution being 
concentrated to small bulk by evaporation. Alcohol was added 
equal*in amount to twice the volume of the solution and picric 
acid carefully added. A crystalline precipitate began to form 
and increased on standing. After 24 hours the crystals were 
15 
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