Kinahan — On Irish Arenaceous Hocks. 553 



Only the washed and weathered-out crop can be seen and ex- 

 amined. How far it extends into the hill, and its quality when 

 followed in, cannot be known unless a level was driven in on the 

 bed. 



[Lewis states there is a similar sand near Lough Salt. This, however, after 

 minute inquiry, I cannot find ; it seems to be unknown.] 



Kane points out that, " In several of the bays of Donegal the 

 sand thrown up by the Atlantic storms is of great purity, and 

 fully equal to that in ordinary use amongst glass manufacturers." 



Donegal sand was used at the Glass Bottle Works, Eingsend, 

 Dublin, " and found very good ; " but owing to the price having 

 risen, the use of it was discontinued. 



In some of the streams westward and south-east of Letter- 

 kenny, there are sands also due to the disintegration of quartzyte 

 or sandstone in situ. Those known are, however, more or less im- 

 pregnated with iron. 



A rather quartzose sand occurs along the railway from Letter- 

 kenny to Derry, at Ballyboe and Monclink. The sand from the 

 latter was largely used as ballast on the line. 



Pit sand for mortar in general is not very plentiful ; it how- 

 ever occurs in Inishowen and near Milford ; while there is inferior 

 pit sand in the neighbourhood of Dunfanaghy and Falcarrah. A 

 very good greenish pit sand occurs a little north-east of Kilma- 

 crennan. A fine sharp sand occurs in small hills in Tullybeg, east 

 of Lough Fern ; while about two miles westward of Eathmelton, 

 in the valley of the Leanane, in small esker-like ridges, there is a 

 clayey sand, used in Bamelton. Hirer sand from the streams 

 and rivers is, however, in general good ; excellent sand for use in 

 Donegal being found in the Dunmurry and Legacorry streams. 

 Other good river sands occur near Glenties ; above Letterkenny, in 

 the S willy ; in inexhaustible quantity in the Foyle, south of St. 

 Johnstown, used in Derry ; in the Finn river, at Lifford ; and in 

 various other places. Good sea sand is got in places along the 

 coast-line. There are on the west and north coasts very extensive 

 dunes and tracts of JEolian sand. 



" Close to the village of Muff, fine sharp white free sand occurs ; 

 used extensively in the neighbourhood and Derry (six miles distant) 

 for scouring steps and such like. In this neighbourhood some of 

 the sandstones are very soft and friable." (A. N'C. Stewart.) 



