106 THE RELATIONS BETWEEN FAULTS, OPEN JOINTS, 



extension of this fault, as farther west, in the 

 Boleyneendorrish Eiver valley we find an outlier of 

 Lower Limestone shale, which has been proved to be 

 bounded on the south by a fault; but the country 

 on the south of the Owenaglanna River is covered 

 with a deep drift or bog, and no positive proof of 

 the westerly extension of the fault was obtained. 



The sixth fault in connection with Slieve Aughta 

 was proved across the low country to the N.E. of 

 Dalystown, and at the eastern end of the Dalystown 

 Eiver valley. This, a little on the north of the village 

 of Tynagh, brings up a tract of Old Eed sandstone, 

 which forms low hills that are well marked, looking 

 at them from the south. This fault has been 

 proved as far as Hearnsbrook on the N.E., and 

 Dalystown on the S.W., but it probably extends 

 much further in the latter direction. 1 



A remarkable north-and-south feature, that is 

 evidently connected with a fault, is the valley of the 

 Barrow, in the S.E. of Ireland; another, having a 

 similar direction, is the valley from Newry to An- 

 trim, in the N.E. of Ireland ; while there appears to 

 be also another, although not so well marked, parallel 

 thereto, extending from Youghal to Thurles, in the 

 south of the island. These three lines of break seem 

 to be of comparatively recent age, as they cut through 



1 Memoir and Maps, Geol. Survey of Ireland, sheets 115, 116, 124, 

 125, and 134. 



