52 REPORT—1862. 
ure, and very difficult to obtain it in any quantity, as its power of producing the 
iiate colour is so great that a very minute proportion suffices to colour the entire 
tissue of a large Boletus, When one of these fungi is treated with ordinary alcohol, 
the aniline it contains is dissolved with several other matters, which, however, do 
not prevent the ordinary characteristic reactions of aniline. This principle appears 
to be present in the fungus as acetate of aniline. I have not extracted it in suffi- 
cient quantity or of sufficient purity to submit it to more than a qualitative exami- 
nation ; but the data which follow will, I think, sufficiently establish the point in 
question. 
case the result is identical for both :— 
Characters of the colouring principle 
of the Boletus. 
1. Colourless. 
2. Very slightly soluble in water. 
3. Soluble in alcohol. 
4. The alcoholic solution resinifies 
sooner or later in the air, becoming 
yellowish. 
5. Does not become blue by ordinary 
atmospheric oxygen unless this oxygen 
is in the state of ozone, 
6. Gives a deep blue colour with 
ozone, or nascent oxygen; this colour is 
ephemeral, and is sometimes greenish, 
passing to wine-colour or rose tint. 
7. Chloride of lime or bleaching 
powder developes the characteristic 
blue or greenish blue given by aniline 
salts. This coloration is ephemeral, 
assing to a port-wine tint, and finally 
isappearing. 
8. Turns deep yellow with hydro- 
chloric acid. 
I give here, in the form of a Table, the characters observed, of the prin- 
ciple extracted from these Bolett, together with the characters of aniline. 
In every 
Characters of Aniline. 
1. Colourless, 
2. Very slightly soluble in water. 
3. Soluble in alcohol. 
4. Its solution resinifies in the air and 
takes a yellow colour. 
5. Does not become blue by ordinary 
atmospheric oxygen unless the latter be in 
the state of ozone. 
6. Gives a deep blue with ozone; the 
colour is ephemeral, and passes to wine- 
coiour ; with some salts of aniline a green- 
ish blue is produced; others give a rose 
tint when exposed to the air. 
7. Bleaching powder developes the cha- 
racteristic blue tint (with some salts of 
aniline, greenish blue). The colour is ephe- 
meral, soon passing to wine-colour, disap- 
pearing with an excess of chlorine. 
8. Turns deep yellow with hydrochlo- 
ric acid, 
These characters suffice, I think, to establish the identity of the principle con- 
tained in Boletus luridus and B. cyanescens with the artificial alkaloid aniline ex- 
tracted from coal-tar. 
nature. 
It is the first time that aniline has been shown to exist in 
The manner in which the blue colour is produced when the tissue of these Boleti 
is broken and exposed to the air is easily accounted for: I have shown in several 
of my former papers (/oc. cit. p. 1) that when oxygen reacts upon organic matters 
in nature, it is generally in the state of ozone. The presence of some ferment in 
the tissue of plants, and in contact with the substance which combines with the 
oxygen, appears to be the cause of this remarkable modification of oxygen. Thus, 
when an apple is cut in two halves, the brown colour which ensues is owing to 
the action of ozone (as may be proved by directly applying the tests for ozone), and 
the ozone is produced by the influence of the ferment: for ordinary oxygen will 
not produce the coloration ; and when the ferment is destroyed by boiling, the colour 
is not produced either. In the case of the Boleti, the aniline which exists in their 
tissue as a colourless salt, turns blue under the influence of ozone produced in con- 
tact with the ferment present in the fungus; for when this ferment is destroyed by 
Wire no coloration ensues when the tissue of the fungus is broken and exposed 
to the air. 
It is well known that some salts of aniline, when exposed for some time to the 
