part 3] THE GLACIATION OF FORTH-EASTERN IRELAND. 371 



overflow-channel, cutting through the watershed and falling south- 

 westwards into the headwaters of the Cleggan River, a tributary 

 of the Braid. The Ci'anny channel is much encumbered with peat,, 

 and contains a long narrow lough known as Cranny Lough. 



The valley of the Glen cloy River is broad and open, and carries. 

 the main road from Carnlough to Bally mena. It opens widely 

 towards the noi'th-east, and received the full thrust of the Scottish, 

 ice, as is shown by the numerous striated surfaces which occur in. 

 the valley itself, on the watershed, and in the valley of the Braid 

 River beyond. All these strise point between west and south, and 

 in many of them it is easy to ascertain that the ice-flow was from 

 north-east to south-west. 



At the head of Glencloy the watershed is cut by four well-marked 

 overflow-channels, all of which fall westwards. Three of these, lying 

 north of the road, connect the Glencloy drainage with the head- 

 waters of the Ticloy Water ; while the fourth lies immediately 

 south of the road, and has two branches at its upper end at 650- 

 feet above the sea. The three northerly channels are all at about 

 the 700-foot level, the northernmost having its intake at 660 feet., 

 the middle one (which is 40 feet deep) at 720 feet, and the 

 southernmost one (which is partly filled with peat) at 750 feet.. 

 These channels cannot well be explained as the overflows of a lake, 

 with the exception of that which lies at 650 feet on the line of the 

 road. The others were probably formed by streams flowing off the 

 ice, at a time when it stood at the level of the watershed, but was 

 unable to cross it. 



The next valley to be considered is Glen arm, which falls from 

 south to north, and at its head divides into two branches — the 

 valley of the Owenacloghy Water on the west, and that of the 

 Linford Water on the east. 



Both these valleys contain much drift, quantities of which are 

 also spread over the broad moorlands wherein the streams rise. 

 Thus, on Douglas Top (1325 feet O.D.) and Glen Head (1287 

 feet) there is drift which appears to contain basalt only, but at 

 800 to 750 feet (in the course of the Owenacloghy Water) are 

 several cuttings in sandy gravel, roughly stratified, and containing 

 basalt, chalk, flint, and Ailsa Craig eurite ; while, lower down the 

 same valley (at 720 feet O.D.) is an excavation in the side of a 

 mound of gravel, which shows current-bedding, and contains basalt, 

 as also numerous pebbles of chalk and flint. 



Red boulder-clay containing basalt and flint is exposed in a road- 

 cutting at 600 feet, three-quarters of a mile north of Park Mill, 

 and in several smaller sections in the same neighbourhood. 



These deposits are all considerably above the level of the Creta- 

 ceous outcrop, and the occurrence of chalk and flint is, therefore, 

 significant. 



The valley of the Linford Water and its upper portion (which is. 

 called Skeagh Water) also contain great quantities of gravelly 



