432 
ON THE SUPERFICIAL STRATA 
ing into small gravel-cover. The scarp of the ridge, formed 
by these knolls, fronts S. This sand-ridge_, reposing on 
impervious till, is traversed by oozing hollows, in which 
some peat-earth has been formed, and is accumulating, 
from decay of moss-plants. Its recesses assume the form 
of small bays, one of which contains the Carron Foundry's 
reservoir. No shifts nor traversing veins have been re- 
marked, and the layers are nearly horizontal. 
At Spittalcroft, on the south side of Stirling, there is an 
extensive sand-pit. The same kind of sand extends to the 
greenstone rock at the town-walls. 
Sp. 13. from gravel cover. 
Sp. 14. sand immediately under. Like those already no- 
ticed, this sand contains granular coal, and exhibits shifts 
at veins traversing the layers. The matters of which it is 
composed serve to shew its relations. Its predominant colour 
is reddish-brown. 
Sands Am> Gravels of the Upper District of 
THE Forth. 
Sp. 15. Above the village of Doune, the gravel exhibits 
calcareous incrustations. At Ashmill Bridge, south of 
Teath Bridge, a small knoll presents all the general fea- 
tures of the sand-hills of Edinburgh. Depth of section 8 
feet. 
Sp. 16. Small-gravel cover, mixed with ochreous earth. 
Sp. 17. Clean gravel and sand under the cover. 
Sp. 18. Sharp large-grained sand. 
Sp. 19. Finer under it. 
Sp. 20. Very fine from bottom of section. All these are 
separated by well-defined Unes of contact, and are not hori- 
