DR. JOHN STENHOUSE ON VEGETABLE PRODUCTS FROM INDIA. 
147 
similar glucosides, which yield the same products when acted upon by acids and 
alkalies ; tannin from nut-galls being equally resolved by acid and alkalies into 
gallic acid and grape-sugar. A solution of datiscetine, when left for some time in a 
warm place in contact with yeast, did not ferment, and though emulsine was also 
tried no separation of datiscetine was observed. 
Action of Nitric Acid on Datiscine and Datiscetine. 
When datiscetine is treated in the cold with nitric acid of ordinary strength, a 
violent reaction takes place, brown vapours are disengaged, and a resinous substance 
produced. The heat evolved by the reaction is sufficient to continue it till all the 
resinous matter is dissolved and a dark red liquid produced, which after boiling 
becomes yellow, and when cautiously evaporated, deposits on cooling crystals of 
nitropicric acid. If the reaction is not carried too far no oxalic acid is formed, and 
the nitropicric acid obtained is very pure, forming large crystals of a pale yellow 
colour. The following experiments show that these crystals are really nitropicric 
acid. 
When treated in the cold with a concentrated solution of hypochlorite of lime, the 
very characteristic smell of chloropicrine is instantaneously observed. The addition 
of a solution of potash to a second portion of the acid threw down crystals of very 
pure nitropicrate of potash, which, when subjected to analysis, gave ]8‘04 per cent, 
of potash, the calculated quantity required for nitropicrate of potash being 17‘66 per 
cent. Datiscine treated in the same way yields nitropicric acid as well as oxalic acid. 
The formation of nitropicric acid by the action of strong nitric acid on datiscine and 
datiscetine, rendered it highly probable, that, by employing dilute nitric acid, less 
highly oxidized products of decomposition might be obtained. Datiscetine was there- 
fore boiled with dilute nitric acid, i. e. nitric acid with ten parts of water; the crystals 
of datiscetine soon dissolved, and a yellow liquid was obtained, which when treated 
with a solution of perchloride of iron gave a blood-red colour. When the original 
solution had cooled, pale yellow crystals were deposited. These crystals were very 
soluble in hot water, and recrystallized on cooling. 
They were likewise very soluble in alcohol and ether, and when deposited by slow 
evaporation from their alcoholic solutions, they formed nearly colourless crystals of 
considerable size, having a fine silky lustre. When treated with hypochlorite of lime 
they did not evolve chloropicrine in the cold, but readily produced that compound 
when gently heated. When they were cautiously heated between two watch-glasses, 
a portion of the substance sublimed in colourless needles. When this acid was 
heated with an insufficient quantity of water to dissolve it, it melted and recrystallized 
on cooling. These properties agree with those of nitrosalicylic acid. In order to 
confirm this hypothesis the following salts were prepared. 
On saturating a solution of the acid with carbonate of baryta, the baryta salt was 
obtained in yellow crystals. From their solution ammonia threw down another 
