On the Contrast in Color. — Croshy. 77 
I have been able during the past year to make two journeys in the 
South — one to Asheville, by the usual route through the Piedmont 
district of Virginia and North Carolina, and the other down the 
great Appalachian valley to the vicinit}* of the Natural Bridge — 
giving, in both cases, especial attention to the distribution of the 
colors in the superficial detritus. 
Briefl\- stated, the general result of these recent observations is 
a complete confirmation of my original views ; but I am able 
now to make more definite statements than formerly. In the great 
majorit}' of the sections observed in the Piedmont region of both 
North Carolina and Virginia, including all which could be de- 
scribed as normal examples, i. e. , as unmodified I)}- disturbance or 
erosion, the distinctl}' red soil is verv superficial, varying in thick- 
ness, as a rule, only from two to five feet, and very rarely exceed- 
ing ten feet. It is usual h' reddest, at, or near, the surface, 
changing downward gradualh', more rareh' aljrupth', through 
various shades of orange to yellow ; while occasional complete 
sections show the yellow changing through paler tints to gray or 
the color of the underlying hard I'ocks. This is certainh* the nor- 
mal succession of colors in a complete vertical section, as described 
in m}- earlier paper. The slight depth — two to five or ten feet — 
reached by the red color was noted again and again in scores of 
sections. It was usually eas}' to see, however, how hasty or un- 
garded observations might lead to a different conclusion ; for the 
wash of the rains has, in most cases, carried the superficial red 
clay down over the entire face of the section. In this way the 
orange and yellow are often almost completely blotted out, except 
where an occasional gully, one to several feet in depth, notches the 
face of the cutting and exposes a clean, fi-esh, undisturbed, vertical 
section of the cla^s. When passing through the railway- cuttings my 
eyes were always focussed upon these gullies or minature ravines ; 
and when on foot I have proved by actual digging that the yellow 
color seen in the middle and lower part of the gullies is strictly in 
situ, and that the red color at the same levels between the gullies 
is what it appears to be, a mere surface wash — a red veil descend- 
ing from the red crown at the top of the section. 
For the past twelve j^ears I have had in my teaching collection a 
series of specimens illustrating the normal gradation of colors 
from the surface soil to the underlying rock, which were carefully 
selected for this purpose at a gold mine in Fluvanna county, Vir- 
ginia ; the entire section, from the surface to the unaltered mica 
