DISTRIBUTION 359 



Overshot run the strikes again change to west of north, following the 

 course of the Gunpowder and Royston branch, the latter curving with 

 the limestone as it wraps around the small anticline near Warren. The 

 dip on the east side of Gunpowder valley is northeasterly under the 

 Wissahickon, in all instances observed, but along the west side there 

 seems to be some slight overturning, the limestones dipping at times to 

 the westward beneath the quartzite, which normally lies below the lime- 

 stone. The exposures in this offshoot from the main limestone valley 

 are rather better than usual, and show with unusual clearness for Pied- 

 mont conditions the shifting stripes" and dips due to the folding of the 

 region. This is particularly true in the area northeast of Warren, which 

 is discussed more fully at another place. 



Worthington valley — Butler area. — The marbles which are so well devel- 

 oped in the valley between Lutherville and Cockeysville extend west- 

 ward from the latter point along the south side of the northern anticlinal 

 dome, widening about 5 miles west of Cockeysville into the Worthington 

 valley, which is in reality the southwestern nose of the northern anti- 

 cline, as already described. The exposures of limestone in the narrower 

 portions of the valley are rather unsatisfactory, but show an east-and- 

 west strike and a dip of 40 to 60 degrees away from the Baltimore gneiss 

 and beneath the Wissahickon schists on the south. In the wider por- 

 tion of the valley the dips become much less, reaching as low as 5 and 

 10 degrees. The strike also changes, as the limestone of the valley wraps 

 around the anticlinal axis, from east to west and northwest and north 

 to east of north. In this part of Worthington valley the natural expos- 

 ures are few, but the solid rock has been exposed in many places by 

 small quarries made for the extracting of limestone for agricultural 

 purposes. 



Extending northeastward from Worthington valley the limestone is 

 found in three well denned bands forming narrow valleys. These dif- 

 ferent bands are representatives of the same formation brought to the 

 surface again and again by the folding of the beds along the level of the 

 present surface of the country. The dips are often steep and sometimes 

 overturned, but the bands unite to form a continuous valley in their 

 southwestern limits. The strike in every instance appears to be parallel 

 to the valleys. The more southerly bands are separated by a synclinal 

 of the overlying Wissahickon, and are in turn separated from the north- 

 ernmost bands by a tightly compressed anticline exposing the Cambrian 

 quartzite and the underlying Baltimore gneiss. These limestone areas 

 do not extend east of the Northern Central railroad, and in only one 

 instance are they found east of the Baltimore and York turnpike. The 

 relations existing along their eastern limit are not determined with 



