QUEENSLAND NATIVE ASTRINGENT MEDICINES. 
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identical with those of the gums of the first group. Boiled with 
dilute hydrochloric acid, the tannin yields the same phlobaphene. 
(3.) The colouring phlobaphene agrees in every respect with the 
gum phlobaphene of the first group, cyanide of potassium especially, 
gives a beautiful vermilion, and ferric acetate a delicate blue colouration, 
in very diluted gum solutions. 
(4.) Gallic acid was found by me to be present to 1-2 per cent, in 
those gums. It was assayed in the same way as that of the gummy 
group. 
Respecting the medicinal value of these gums, it must be stated 
that they are the remedies most adapted to be used in the inhaler. A 
10 per cent, solution is the fittest for this purpose. As an internal 
medicine, a 5 per cent, solution will generally do, but if it does not act 
quick enough there is no harm in dissolving half-an-ounce of the gum 
in a 6-oz. bottle, to be taken in twenty-four hours. For external pur- 
poses gums of this group might be mixed with two parts of gums of 
the siderophloia group, to strengthen the effect of those. Very good 
results have been obtained by me in this way. 
III. The turbid group of Mr. Maiden contains a large number of 
gums in the Moreton Bay district, including Eucalyptus corymbosa , 
E . maculata , E . tessellaris,E. microcorys. It includes also the gums 
of the Angophoras — viz., A. lanceolata , A. Woodsiana , A, subvelutina. 
The gums of this group are of the highest interest to the scientific 
chemist. They contain one or two tannins derived from gallic acid, 
and yielding pyro-gallol by dry distillation. None of the gums of this 
group contains the slightest trace of catechin or kino-tannic acid. They 
are all coloured blue by ferric acetate. Some contain a high amount 
of benzoic acid, which can be easily sublimated out of the fresh gum. 
A resinous matter is often present, derived from the tannin contained 
in them, or in some cases to be considered as derived from the essential 
011 of the leaves, and acting as mother substance to the tannin. We 
begin the description of these gums with that of the Angophoras. 
(1.) Angophora lanceolata does not contain any essential oil in 
the leaves. It has a smooth bark much like that of Eucalyptus 
maculata , and resembles that of E. tereticornis and E. hcemastoma. 
Between wood and bark a gum is exuded, being lignified by rains and 
run into red brittle streaks. When dissolved in water, it behaves 
much like that of A. subvelutina , leaving a whitish insoluble powdery 
deposit. It dissolves to a great extent in hot water, but the solution 
always looks turbid. A piuky white precipitate occupies the whole 
volume ot the liquid. 
Angophora gum is partly soluble in cold water, and out of this 
clear solution, after some standing, a white powder is deposited, 
insoluble m cold alcohol, ether, and acetic ether. Under the micro- 
scope (750) it is seen to consist of a granular mass of ellagic acid, 
which dissolves in caustic potash with intense yellow colour, getting 
darker and darker till it approaches to blood-red. After a minute or 
two, groups of radiating needles of potassium glaucomelanate are 
formed, and single needles are seen to grow rapidly iu the yellow 
solution of the ellagic acid. Fuming nitric acid dissolves the powder 
with intense crimson colouration, and sulphuric acid makes a yellow 
solution by addition of water. In hot alcohol the powder dissolves 
