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A peculiar reaction, which I have not seen mentioned in any of the works at my disposal, is that 
the sample of saponin prepared from the beans, on the addition of ammonia, dissolves in the cold with a 
beautiful carmine colour', which appears only gradually, and gets more brilliant as exposed to the air. 
After a while the colour begins to fade, and remains yellow ; when heating the red colour disappears 
rapidly. The saponin itself is not changed, as, on evaporation of the ammoniacal solution with sulphuric 
acid again, the characteristic glucoside reaction is obtained. Weak caustic potash dissolves a trace of the 
saponin with a brick red colour, also changed into yellow on standing or heating. I don’t know if this 
peculiar reaction is due to the impurity in my samples of saponin or not. The air-dried sample of the 
bean was also tested for alkaloids, but no trace of a bitter principle can be found in alcoholic extract or 
acidulated alcoholic extracts. That the substance obtained from the hot alcoholic soluble extract is really 
a true saponin, is further proved by the fact that a solution of it does not reduce Fehling’s copper solution. 
When heating a solution with dilute acids for some time, the saponin is decomposed into glucose, and into 
a substance, saponogin, sparingly soluble in water. The inverted saponin solution, due to the presence of 
glucose, acts at once on Fehling’s solution. The saponogin is soluble in hot alcohol, and forms, on 
evaporation, a crystalline residue. 
I consider the presence of a saponin in the beans undoubtedly proved, and the toxic effects of the 
bean are due to this glucoside. 
As saponin is very soluble in water, it also shows that by soaking the crushed beans for a few days 
in water, as practised by our aboriginals before using the seeds as food, the poisonous principle is removed, 
leaving a rather valuable nutritious food. 
Bark. —The bark is smooth, dirty gray externally, pale brown or yellowish internally. A tree 
2 feet in diameter has a bark, say, J inch thick. It is not astringent, and therefore not to be thought of 
by the tanner. It is, however, bitter to the taste, and probably contains saponin, though I have not 
chemically examined it. 
I wrote the above words concerning the hark in the Agricultural Gazette, 
N.S.W., Jan., 1891, p. 3, and it is interesting to find that, in 1901, Mr. Brunnicli 
found a saponin in the seeds. 
On the bark may be observed numbers of lenticels. These are organs 
(usually slightly raised) frequently found in the periderm of both stems and roots. 
They correspond to the stomata of the epidermis (commonly that of the leaf), and 
serve, like them, to admit air to the living internal tissues. 
Timber. —It is easiest described by stating it strongly resembles walnut. I 
have always endeavoured to urge moderation in advocating the claims of colonial 
timbers, feeling sure that our timbers have received a good deal of harm from 
indiscriminate praise; but, having kept black bean under observation for a number 
of years, and having caused large quantities of it to be worked up into various 
articles, I think very highly of it. I look upon it as scarcely inferior to walnut. 
People sometimes complain of it that it warps and splits a little, but it does not do 
this if it receives the seasoning that cabinet woods receive in the northern hemi¬ 
sphere. Let black bean be felled when the sap is down, and given a reasonable 
amount of seasoning, and I do not hesitate to say that it may be pitted against 
walnut without disgrace. Black bean is easier to dress than even cedar; in fact, it 
is almost perfection as regards the ease with which a surface can be got on it. It 
polishes readily, but the grain is inclined to rise under polish. This timber often 
shows a beautiful figure; planks which have the figure in bands, like the marking 
of an agate, are really gorgeous. 
