COLORING MATTERS OF LEAVES AND FRUITS. 
33 
with an excess of the coloring matter. If the natural color 
were blue, the solution should then become blue, and not red, 
because all the free acid is saturated. The coloring matter, 
on the contrary, as we have seen, forms with the malate or 
citrate of lead a combination which is of a beautiful clear 
blue; but this color does not exhibit any of the peculiar shade 
of the coloring matter; dissolved in alcohol, it may be pre- 
served without oxidation. It does not oxidate, however long 
it may be kept in contact with the free acids in the juice of 
the fruit. The brownish-red deposit is slightly soluble in 
water; its solution is of a deep red, but potassa forms with it 
a deep brown solution. It forms with ammonia a neutral 
soluble combination, and an insoluble, or but slightly soluble 
acid, of a reddish-brown color. The neutral green combina- 
tions of the pure red coloring matter change, while in a moist 
state, under the action of the air, into this brown combina- 
tion. The precipitate by lead is, however, an exception, 
since it is permanent, both during washing and drying. I 
have kept, without alteration, for six years, the green preci- 
pitate obtained from the bird's service, {Sorbus acuparia,) 
by means of acetate of lead, the malic acid having been pre- 
viously separated by carbonate of lead. 
3. The red coloring matter of leaves in Autumn. 
We perceive, in the autumn, the leaves of certain trees to 
become red. All trees and bushes upon which I have seen 
these red leaves, bear red fruit: {ex. Sorbus acuparia; Pru- 
nus cerasus; Ribes grossularia, var. rubra; Berberis vul- 
garis, &c.) The red color which they contain is so much 
allied to the preceding, that they may be considered as iden- 
tical. However, I have only examined the foliage of the 
cherry, and especially the red currant. The leaves of this 
latter becomes ofttimes so red as to have the appearance of 
the ripe fruit. The coloring matter was extracted by alcohol, 
which, after distillation, left a red liquor, from which, by fil- 
tration, a resin and a fatty precipitate were separated. The 
filtered liquor was mixed with water, without being troubled, 
vol. v. — NO. 1. 5 
