238 
TasBLE 1V.—Jsolated Granites. 
Perox- Loss 
Locatiry. Silica, | Alu ide of | Lime. Le ea by Ie-| Torat. 
——— — —_ SS os 
1.Cushbawn, . . .| 70°32 | 11-24 | 4°80 | 3-01 0-73| 2°27 | 3:39 | 1°62] 97°36 
2. Croghan Kinshela} 80°24 | 13-24 | 0°72 | 0°89 |Trace| 0°40 | 5-58! — |101-07 
3. Ballymoty,. . .| 66°60} 13-26 | 7°32 | 3°36| 1:22 2°31/ 3°60| 2°34 100-01 
4, Ballynamuddagh, | 68°56 | 14-44 | 5-04 | 3°85) 0°43 2°78 | 3-36| 1-00| 99°46 
} ! 
“No. 1. Cushbawn.— Specific gravity, 2°671; a fine- 
grained granite, containing hornblende in addition to mica. 
Besides the constituents given in the Table, the specimen ex- 
amined by me contained 1°34 per cent. of carbonate of lime. 
«No. 2. Croghan Kinsheia.—Specific gravity, 2°629 ; this 
granite is composed of quartz, feldspar, and chlorite. The 
specimen examined appeared to be composed exclusively of 
quartz and feldspar. From the great quantity ofsoda, I infer 
that the feldspar of Croghan _Kinshela is probably albite. On 
the northern slope of this mountain are situated the old gold 
streams of Wicklow. 
“No. 3. Ballymotymore.— Specific gravity, 2°659 ; a very 
fine-grained granite, but containing distinctly feldspar, quartz, 
and black mica. 
‘No. 4. Ballynamuddagh.— Specific gravity, 2°670; a 
coarse-grained granite, with large plates of black mica. 
*¢ Applying to the preceding granites the method of caleu- 
lation already employed, we find, excluding the granite from 
Croghan Kinshela, which contains chlorite in place of mica—- 
TaBLE V.—Atoms of Granitic Minerals. 
Atoms | Atoms |Atomsof] Atoms | Atoms | Atoms 
LocaLirTy. of Silex jof Perox-| Protox- of of Feld- of 
=a. {ide =b.|ide =c.| Quartz.| spar. Mica. 
Cushbawn, . . .| 1°529 0-278 | 0300; — —_ — 
Ballymoty,. . .| 1:448 | 0°349 | 0°346 | 0-067 | 0-343 | 0-003 
Ballynamuddagh, | 1°490 | 0°344 | 0°325 | 0:209]| 0°306 | 0-019 
