54 
On stronger heating comparatively much volatile oil goes over 
miscible with the most solvents, floating on water and having the 
smell like that of Olewm carvi with a little of that of Olewm terebin- 
thine. 
ANALYSIS— 
Volatile oil 
| See 
Sonor 
_ it becomes soluble in benzine and oil of turpentine, 
Heated with one-third of linseed oil and three-fourths of oil . 
turpentine it gives directly a clear varnish fit for the most delics 
uses. ) 
ASTRINGENT GUMS. 
Acacia harpophylla, F. v. M., Fl. Austr. ii. 389. Brigalow. 
This Queensland brigalow yields a light or dark-brown gum, which #4 
highly interesting to the scientific chemist. It has a sour, astringen! 
taste, and is entirely solublevin cold water, forming @ mucilage ‘ 
sticky as that of arabic gum. It has a specific gravity of 1:06, an 
contain: per cent. of water. 
_ The “ brigalow-arabin,” which forms the bulk of the brigalow 
is so closely united to the catechutannic acid contained in it, that it 1 
almost impossible to separate one from the other. Not arabin 
precipitated from a brigalow gum solution by alcohol, but the at ne 
united with the catechutannic acid, in other words, the whole brigi 
: ees further on). +2 
uite black by ferric salt). If only a small amount © HCl. is added 
the solution of the brigalow gum, it no more falls down with alcoho, 
_The (white) precipitated gum in alcohol js dissolved quickly 08 
addition of a few drops of HC, and it falls out (yellow or brow) 
the solution is neutralised (with KOH). A small excess “= the 4 
it fall down again. Ferric chloride not only precipitates ee —s 
nnin, it also coagulates the “brigalow arabin” unite = 
tannin, that is to say, the whole brigalow gum 
cheesy mass (from a th 
tion, and in this alkaline solution a fresh precipitate is form 
aleohol. This precipitate after prolonged washing 
KOH. 
e tannin of the brigalow gum is present from 3 to 6 
th alcohol in 8 
percolator yields the pure brigalow arabin. It gelatinises with ih : 
and a : 
per cent.; low percentage is the rule. The tannin differs from ” 
: snifolia, A. Cunning 
pared), an 4 of 
