BUTLER COUNTY. 395 
The vegetation is imbedded in the clay very often, and part of it shows 
that it has been subjected to rough, mechanical agencies. The frequent 
presence of leaves and roots in or upon the deposit serves to show, how- 
ever, that the source of the vegetation was not very far removed. The 
north bank of Elk Creek, opposite the mill at Miltonville, also gives a 
fine exposure of the clay. At this point a peculiar modification of the 
bowlder clay is found that deserves particular mention. It is a clay dis- 
tinctly green in color, and, as shown by a single analysis of a specimen 
obtained at this point, is very rich in potash and soda. The analysis 
made by Prof. Wormley is here subjoined: 
Via lLOPRCORDINOG seas sae ter sia sat mekelacies sisfaicitais necicisieelocimissicie cs le ck 4.58 
Silicic acid ...-.- 1 SHOES OOOO OE COR COO COC ODE TODO Fe BOOED OD EE CaS SIGE EE es 59.10 
ROMESESGUIO IC Siemon se lo ssniesselecsaia cca) ca ae lciauicinial als alate lalelavls sla 6.79 
JA Teron 5 ies en gaa ee le A ae UP oO eae 19.41 
Garpormabero telimone een sierra ae elem enata cu Medae Micha eta a Ho 4.58 
Silscaterot@limverecesn seman etl ee ene iid ae ean pa hg reget oe RS GN a 3.00 
MECIOSID soso seosbb bono bed pobboD pocdoolboddon bedocd os0080 Goudud os05 60 0.82 
MotashvandesGdayseeseemrceee eres siesacisssiaie selete celal eweteia HOO BBO Se OSS 4.95 
99.67 
It will be seen that the elements above named, viz., potash and soda, 
are abundant enough here to make the clay a fertilizer of considerable 
value. Vivianite, or phosphate of iron, is of frequent, perhaps constant, 
occurrence init. Vegetable matter is also always present. This green 
clay has been more frequently met with in Warren and Butler counties 
than elsewhere. 
The vegetable matter that is intermingled with the bowlder clay is to 
be distinguished from that which is borne upon its surface. The pres- 
ence of a buried soil of inter-glacial age has been repeatedly mentioned 
in the reports on this Geological District. Hxamples of this ancient soil 
are not wanting in Butler county. An interesting case of this sort is 
recorded by David Christy, Isq., in his Letters on Geology, published in 
1848. In the last letter of the series, page 5, he says: 
‘‘ Beneath our Diluvium are occasional beds of ‘hard-pan or very tough blue elay, 
with imbedded pebbles.’ I had my attention directed to this new and interesting fea- 
ture of our Geology last summer by Robert Beckett, Esq., eight miles east of Oxford. 
He called upon me to examine the stump of a tree standing erect in this deposit at a 
point where a small stream is encroaching upon a bluff. The roots penetrated the hard- 
pan in all directions. ‘Twenty feet of Diluwium overliesit. We dug out the stump and 
a part of the roots. Some years since, Mr. B., in digging a well twenty or thirty rods 
distant from this point; at a depth of ten feet in the Diluvium, struck upon another small 
