50 The Rev. S. Haughton’s Notes on Mineralogy. 
Per cent. Atoms. 
Bilidg oul soe) 2~ BRBO wee da UB 
Alumina. . . 6°54 pnts 0-199 
Peroxide of iron. 5°82 0:073 
Lime(carbonate). 1°81 
Magnesia. . . 0°60 0:030 
Patasbyoti+ dion 60 0:078 +0:206 
Soda oe < Goy@eQe 0-098 
Winter t. veer. alee 
99°81 
This rock, like that at Ballymurtagh, Co. Wicklow, is a com- 
pound of quartz and felspar ; if it be regarded as a sedimentary 
rock, it must be considered as a trappean ash, composed of fel- 
spar and fine quartzose mud, with a slight admixture of carbonate 
of lime. Its mineralogical composition is as follows :— 
Per cent. 
6) ae meinay eo 
Orthoclase felspar. . . 57°19 
Carbonate oflime. . . 1°81 
99°81 
3. Siliceo-felspathic Traps of Benaunmore, Co, Kerry. 
The hornstones or siliceo-felspathic rocks of Benaunmore 
occur in splendid columns, many of which, as described by 
Mr. Foot, of the Geological Survey, are 200 feet in length. 
The rock is more translucent than the felspathic traps of Wick- 
low or Waterford already described, and presents more of the 
character of a truly igneous product. Its analysis gave the fol- 
lowing results :— 
Per cent. Atoms. 
Silicacs) cee fee fee ee DOAN 
Alumina . . . 12°24 pean 
Peroxide of iron. 3°16 0:039 
ime 6) zee | O84 0:030 
Magnesia. . . 0:39. OO19[,, 
Potash. 2 2 2 865. 0:90 AMAR 
Boda: Ph Sieur: S86 0°109_ 
Loss by ignition. 1°20 
98°36 
This rock, like the others already discussed, is a compound of 
quartz and felspar ; and it is easy to calculate the proportions of 
the two minerals as follows :— 
Per cent. 
Ghagrtan yt dy ae aw RDS 
Orthoclase felspar. . . 77°85 
98°36 
