H. Morton on the Color of Fluorescent Solutions. 199 
fluorescing matter might have been absorbed by the charcoal, 
1 i t. 
duced to a rich yellow, the fluorescence appears green. The 
same result follows from filtration through bone black, with a 
marked increase in the amount of fluorescence visible, as the 
light-absorbing coloring matter is removed. By continuing the 
decoloration until the liquid is colorless or of a very light tint, 
its fluorescence is distinctly blue. 3 : 
The results with the spectroscope when it was applied to this 
substance, were the same as with the solution of asphalt. 
Such also is the case with tinctures of chloro hyl, which, when 
fresh and green, gives apparently a green light, and, when old 
and brown, a gray color. 
uite differently, as in the case of nitrate of uranium, and pos- 
sibly the fluorescent material in the asphalt, which may be rela- 
ted to the solid hydro-carbon fluoreseing green, which Becque- 
tel mentions (La Luminere, tome i, p. 3 : 
In this general connection let me mention that I have 
observed that while the acid salts of quinine generally are fluo- 
the chloride is not, and that hydrochloric acid will de- 
Compose the acid sulphate so as to destroy its fluorescence. 
ere are several other points in connection with this and 
one foregoing subject, which I must leave for a subsequent dis- 
Ussion, 
July, 1871, a 
ey S—Aug. 1st. I have just obtained results with turmeric 
Which seem to indicate that its Auorescence is due to the pee 
®nce of a substance not yet observed, soluble in water, an 
“Rout any color. 
