ON THE FRUIT OF DIOSPYROS VIRGINIANA. 165 
113 grains. The whole was completely soluble in water, 
and did not contain a trace of apotheme. The residue left 
when the tincture was filtered was now examined, and 
found to consist of ligneous matter, completely enveloped 
in a gelatinous mass ; this was submitted to the action of a 
solution of caustic potassa ; the liquor was immediately co- 
loured deeply brown, almost black ; after dissolving all the 
soluble matter, it was filtered and neutralized with nitric 
acid, which rendered the solution nearly colourless, and 
threw down a copious precipitate ; this was dried, and 
weighed IS grains. The remainder was ligneous matter, 
and when dry weighed 11 grains. 
In all the former experiments there was found to be a 
considerable quantity of tannin in the persimmon ; and when 
the tinctures were evaporated, the tannin, all of which had 
been dissolved by alcohol, was changed into an insoluble 
apotheme ; but in the last experiment there was not a trace 
of tannin in the persimmon, nor yet of apotheme formed from 
the tinctures, but it was left with the lignin when the tinc- 
ture was filtered ; that this was apotheme, was inferred from 
the colour and general appearance, from the brown colour 
which it caused in a solution of caustic potassa, and from 
its precipitating, when the solution is neutralized by an 
acid, all of which are mentioned by Berzelius as being cha- 
racteristics of apotheme. The apotheme from this experi- 
ment weighed IS grains, which is nearly three per cent, on 
the persimmon employed. In a former experiment the apo- 
theme was five percent., so that the tannin is partially con- 
verted into sugar, but three-fifths of it is formed into apo- 
theme and remains as such in the ripe fruit. There was 
also a considerable diminution in the quantity of lignin as 
compared with a former experiment, in which it was found 
to form one-twenty-seventh of the whole fruit; but in the last 
experiment it was only one-fifty-fourth. Now it is sup- 
posed that in the young fruit lignin serves as a sort of 
frame-work, and is a means of circulation for the juices of 
16* 
