Perryville, Md. Walk along P.R.R. track from Perryville to Charleston then across county to B.&O.R.R. and north to Perryville. Distance 14 miles. See paper "The Stratigraphy of the Potomac Group in Md." Clark - Kittredge. Section 1 1/8 miles E. of Principio Creek (P.R.R.) Recent Loam with gravel 5' Raritan Fine white sand. 11' Loam Brown loamy sand, bearing gravel at certain horizons base 12' Cretaceous Potomac. White clay, somewhat dim stained and variegated; at times graduating over into micaceous sands; changing to gravel, calcareous conglomerate horizon base — 10-20' Dense variegated clay. 10. Jurassic Patuxent under ground. Fogs Hill on B.&O.R.R. Potomac. Buff sands, water having off base 25' Dense variegated clay 10-30. In places with considerable pebble. The upper zone always with pebbles.