red 
J/) 
This phenomenon is to be explained by observing the absorption 
curves (fig. 1)'); the curves of the two para-derivatives, which are 
rig, 1 
OSCILLATION FREQUENCIES. 
2000 22 24 26 28300032 34 36 38 4000 42 44 
Logarithms of equivalent thicknesses 
of N/10.000 solutions 
m-Nitro-aniline. 
eener m-Nitro-dimethyl-aniline. 
me, nf es p-Nitro-aniline. 
ea as p-Nitro-dimethyl-aniline, 
Fig. II. 
OSCILLATION FREQUENCIES. 
2000 22 24 26 28300032 34 36 38 4000 
of N/10.000 solutions. 
Logarithms of equivalent thicknesses 
3.5. Dinitro-p-toluidine, 
weeer 3.5. Dinitro-dimethyl-p-toluidine, 
eid 2.6, Dinitro-p-toluidine. 
—,—,— 2.6. Dinitro-dimethyl-p-toluidine. 
') Baty, Tuck, and MARSDEN, J. Chem. Soe. 97, 582 (1910). 
