KiNAHAN' — On the Clearing of Peaty Waters. 451 



snow. On visiting tlie Ballynagappoge brook if: was found that the 

 ■waters were quite colourless and clear. Up to the head waters above 

 Ballynagappoge-bridge no peaty colouring matter could be detected ; 

 the snow did not reach as low as this bridge. 



It should be mentioned that though in cold weather little peaty 

 colouring matter is in the streams, yet in the bog-holes (turf -holes) the 

 water is quite brown. 



The Carawaystick brook may be next described, as it is an example 

 of a different class. Along its course very little diminution of the peaty 

 tint occurs, though there is every facility for oxidation ; the brook 

 descending a height of about 1200 feet in a flow of less than two 

 miles. 



This brook flows from Kelly's lough, a small sheet of peaty water 

 about eight acres in extent, on the S.E. slope of Lugnaquilla at an eleva- 

 tion of about 1700 feet above the sea. On the S.tV. of the lough 

 there is a granite cliff ; the brook leaves the lough at the JN'.E. corner, 

 flowing through the remains of an ancient glacial moraine in a north- 

 westerly direction, for over a mile, with a slight inclination, then for 

 the rest of its course (about half a mile) it descends a height of 700 feet 

 (calculated by aneroid) over a bed composed of granite and schist, by a 

 succession of falls and rapids, the waters being lashed into foam down 

 nearly all that part of its course. From a comparison of samples 

 taken both above and below the falls, no difference could be detected 

 in the depth of tint of the waters. 



During one of our visits, after there had been no rain for three or 

 four days, it was remarked that the waters were not nearly so deeply 

 coloured as on a previous visit, when showers were falling on the 

 mountains. On this occasion, before ascending, a sample of water 

 was taken at the foot of the falls, then about a cubic yard of a sandy 

 clay was put into the stream above the fall, rendering it very turbid ; 

 then taking a second sample of water just above the turbidity, we 

 descended to where the first had been taken from, and here after the 

 turbid water had been flowing for some little time a third sample was 

 taken. On comparing the samples subsequently, after the turbidity 

 in No. 3 had completely subsided, this sample was darkest, while there 

 was no apparent diiierence in tint between IS^os. 1 and 2. 



Along the Avonbeg the changes that occur are irregular, although 

 on the whole there is a diminution in the depth of tint as we descend 

 to the "Meeting of the Waters." Here it is joined by the Avonmore, 

 and in a sample from this latter river, taken here in May, 1880, a 

 small quantity of lead (0-028 parts per 100,000) was detected. 



The united Eivers Avonmore and Avonbeg form the Ovoca, which 

 a short distance down receives the waters from the Ovoca mines ; fixst 

 on its east or left bank, from the mines of Tigroney, Cronebane, and 

 Connary ; these containing ferrous sulphate, and sulphate of alumina 

 in comparatively large proportions, Avith smaller quantities of other 

 salts, as sulphate of copper, and arsenic. Lower down the river, 

 coming in from the west or right bank, is the drainage of the Bally- 



R. I. A. PROC, SER. n. VOL. III. — SCIENCE. 2 P 



