391 



hydrochloric acid, and boiled. The acid melted in the hot water, forming a 

 semi-fluid mass, and when cold it was a solid lump of a sulphur-yellow coloured 

 resin. The process was repeated, but only a trace of the pasty salt was obtained 

 the second time. 



The acid was purified as follows : — It was powdered, dissolved in the smallest 

 quantity of alcohol, neutralised with an alcoholic solution of soda, water added, 

 and the alcohol removed by boiling. When cold, sufficient lo per cent, aqueous 

 soda was added to form an abundant precipitate ; it was then heated until the 

 precipitate had dissolved, and allowed to cool. When cold, the greater portion 

 of the acid had precipitated, and no further precipitate was obtained on the addition 

 of solid caustic soda. The sodium salt, which was minutely crystalline, was then 

 dissolved in water, acidified with hydrochloric acid, and boiled. The resin readily 

 melted in the hot water, but when cold was very brittle and powdered readily* 

 This process was repeated three times, the resin being finally obtained of a 

 sulphur-yellow colour when in the lump, but when powdered was almost colourless, 

 being only slightly tinged yellow. It was finally dried on a porous slab and heated 

 in a melted condition on the water bath for some time until thoroughly dry. This 

 freshly prepared resin melted at 77° C. ; another sample prepared specially from 

 a fresh portion of the resin also melted at 77°C., but the melting point slowly 

 increased until after one month or five weeks it had reached the melting point 

 99-100° C, and after some months ioi-i02°C., which appears to be the stable 

 melting point. It was readily soluble in 70 per cent, alcohol in the cold, and in 

 organic solvents generally. On addition of water till turbid, and slowly evaporating 

 in the air, no crystalline product was formed, the separated resin being quite 

 amorphous, and by no process could a crystalline substance be obtained with 

 this acid. 



The purified acid -was dissolved in chloroform, acetic anhydride added, 

 and afterwards one drop of sulphuric acid ; the solution instantly became of a 

 deep purple colour, which soon changed to a purplish brown. This colour reaction 

 differed from that of the corresponding acid of Armicaria Cunninghamii in being 

 less violet, and in changing to purple-brown after a short time, instead of to an 

 olive-green colour. 



The acid was dextro-rotatory in solution ; and i gram dissolved in 10 c.c. 

 alcohol rotated the ray 2-15° to the right, the specific rotation was thus [aj^ + 

 21-5°. Another determination from freshly prepared material gave identical 

 results. 



0-2311 gram acid dissolved in alcohol required 7-55 c.c. decinormal NaOH 

 to neutralise it ; therefore 40 grams would neutralise 306 grams acid. 



0-2777 gram dissolved in absolute alcohol, required g-15 c.c. -NaOH to 

 neutralise it ; therefore 40 grams would neutralise 303 grams acid 



