FANT) aai | ite 6) Eee 
THE OWALA SEED AND OIL. 305 
degree the nature of the colouring matter, or that to develope the red 
colour some matter insoluble in ether was necessary. If so, this would 
be found in the etherized residuum. That the last supposition was 
correct will be seen from the following experiment :—Having exhausted 
with ether a certain quantity of kernels, and dried the insoluble resi- 
duum, I recovered it again with alcohol boiling. I subjected the alco- 
holic extract to evaporation, and there remained a viscous mass very 
similar in appearance to molasses, which become brown when I added 
alittle sulphuric acid. 1 mingled a little sugar syrup with the oil ob- 
tained by ether (which, as I have said, took only a light violet tinge), 
and poured on the mixture some concentrated sulphuric acid. The mass 
speedily took first an olive and then a red colour; in fact, the result 
Was the same as in the case of the kernel itself. As I perceived that 
the absence of sugar was the cause of the etherized extract not deve- 
loping the red colour on the application of sulphuric acid, I conceived 
the idea of replacing the natural saccharine matter of the seed by com- 
mon sugar. Experiment encouraged that idea, for the result in all 
tases was the same phenomenon of red colour, and therefore the pre- 
Sence of sugar is absolutely necessary to produce it. After I ha as- 
certained in what parts of the kernel that red colour could, by the aid 
of sulphuric acid, be produced, I was desirous of assuring myself whe- 
t er exterior agents had any influence on the production of this phe- 
nomenon, I first tried the effect of light, and for that purpose:ex- | 
.. posed one portion of the mixture of the nut and acid to the rays of the 
Sun, and kept another portion in darkness. In both cases the red 
colour made its appearance after a short time, with nearly the same 
degree of intensity. The next agent experimented upon was the at- 
x mosphere, and two quantities of the solution were kept, the one in the 
Open air, the other in an hermetically sealed vase. The result was that. 
it the latter no colour made its appearance, while in the former it was 
"ey vivid. At one time I fancied that the colour was attributable to 
the admixture of a small quantity of water, but further experiments 
Proved that water was of no service, that oxygen alone of all atmo- 
spheric agents had any influence. The path of a current of air passed 
|. ver the mixture of oil, sulphuric acid, and saccharine, could be traced 
the appearance of the bright red-crimson on the parts of the surface 
: “posed to its influence. The pulp, divested of oil by the aid of ether, 
es Contains albumen, more or less coagulated ; an albuminous matter that 
E. VUL 1, x 
