Dr Boue on the Geology of Central Tvrkey. SS 



the inclined bed of limestone and the granitoidal gneiss ; it even 

 forms a small distinct vein in the limestone, which is partly pa- 

 rallel to the direction of the bed. This gives rise to the most 

 singular juxtaposition of the rocks, and to mixtui-es of the gra- 

 nitic or felspathic and siliceous matter with the limestone, being 

 nearly of the same kind as the well-known instance in GlentUt, 

 and at Brevig in Norway, between sienite and limestone. The 

 granite is always separated from the white marble by three 

 zones of greater or less thickness and regularity- The first 

 zone or stripe is a granite with green augite, and also some- 

 times penetrated with calcareous matter ; the second is a beau- 

 tiful mixture of red or yellowish garnet, crystallized or massive, 

 Vesuvian, a little greenish augite, and a large quantity of grey- 

 ish or bluish quartz or amethyst, as also, although rarely, ga- 

 lena ; the third consists of granular limestone, with nodules, 

 veins, or nests of the same mixture of quartz, Vesuvian, and 

 garnet, with fibrous tremolite like that of Glentilt. This last 

 often forms the exterior crust of the nodules of quartz and 

 other minerals. I collected at this place some most singular 

 specimens of rocks, as, for instance, limestone with pegmatite 

 veins, slate with the same and stripes of compact garnet, very 

 beautiful compact rose garnet rock, like that of the Pyrenees, 

 beautiful hornblende and chloritic rocks, granite with epidote 

 and rock-crystal, cavities of calcareous-spar in the limestone 

 next the granite, granite, Avith nodules of a greenish mineral, 

 probably augite, mixed with black mica, limestone with felspa- 

 thic spots, siliceous felspathic matter, and the like. The fol- 

 lowing is a cross section of the rocks from W. to E. : Gneiss of 

 a granitoidal nature, granite, limestone, granite, limestone, gar- 

 net rock with pegmatite, gneiss with veins of pegmatite, chlo- 

 ritic and hornblende rocks, slaty argillaceous rocks with veins 

 of granite, gneiss with veins of granite, granitoidal gneiss with 

 the same veins. The rest is covered by debris and forests. 

 The limestone is evidently a bed in the gneiss, for at a quarter 

 of a league to the E. of the Convent of Rilo, the same kind of 

 limestone occurs in gneiss as a bed of fifteen or twenty feet in 

 thickness. In one quarry at this place, the strata, reckoning 

 from below upwards, are as follows : Gneiss with nodules of 

 pegmatite, granular limestone mixed with silica, ten feet of 



