198 Hf. Morton on the Color of Fluorescent Solutions. i 
Some, at least, of these features, are traceable for miles in 
the longitudinal extension of the zones in which they occur 
Thus the prehnitic amygdaloid of the Isle Royale series, is 
found in the N.E. extension of this zone, near where the road 
to Hagle river crosses the line between Townships 55 and 56 
N., or about 7 miles from Portage Lake. 
The coarse-grained melaphyr of the “ Dacotah,” is found 
extensively developed in the extension of the same zone on 
the South-Pewabic, Quincy and St. Mary’s properties. The 
brown amygdaloids of the “Southside” reappear with their 
peculiar scoriacious structure in the South-Pewabic and Han- 
cock beds, and in the trenches on the St. Mary’s, and have been 
considered the equivalents of the “ Ash-bed” rocks of Kewee- 
naw county, which they resemble. 
[To be continued.] 
Art. XXVIIL— Observations on the Color of Fluorescent Sol 
tions ; by Henry Morton, Ph.D., President of the Stevens 
Institute of Technology. 
familiar fluorescent solutions, such as the tincture of turmelt, 
of agaric, of chlorophy], and the solution of nitrate of uraniull, 
a specimen of mixed asphalt, which is here largely used in - 
aration of pavements, a a light-yellow solution me 
lue, and 
spectrum, as compared with the blue fluorescence, but only 
absorption of the red and violet ends. When, however, a ple® 
rescing canary glass or solid nitrate of uranium 
1, the green light was (as is well known) largely au 
I also found that when, by filtration through animal char 
aoe in turpentine was reduced in color, the gree 
a fluorescence dis _— in a corresponding 
_ This alone would, however, have proved ithe as a 
