APPENDIX. 



^ 



blende rock, there are rugged cliffs of micaceous schistu.9, 

 which is in some places alternated with quartz, and in others 

 traversed by considerable granite veins. The micaceous schis- 

 tus sometimes contains garnets; and the granite, which is 

 great-grained, frequently contains crystals of schorl and 

 mica, and sometimes k has the appearance that is called 

 pierre graphique. Such appears to me the disposition and na- 

 ture of the strata upon the shore o.t Portsoy*. 



ff As the geognostic el-rii-M' + -TS of the serpentine at this 

 place are interesting, I shall here mention, for the information 

 of my readers, a few taf.t*, which show that pretty nearly 

 similar appearances have been observed in other countries. 

 Zobtenberg, in Lower Silesia, consists entirely of serpentine, 

 in which some hornblende is found, and its strata are nearly 

 vertical f. In the Miner's Kalendar for 1790, Kohler in- 

 forms us that serpentine and primitive limestone (marble) 

 are nearly allied in their geognostic characters, and that 

 sometimes they are disposed in strata which alternate. We 

 are also informed that serpentine rests upon gneiss, and even 

 alternates with it t, and also with quartzy talcaceous schistus . 



" The appearance of the veins of granite t? aversing horn- 

 blende rock and micaceous schistus, is by no means uncom* 

 mon in Scotland ; and in other countries similar appearances 

 have been very often observed. The pierre graph' que has 

 been observed in Siberia to form the sides of veins where the 

 topaz is found [| j but at Sebritz it is disposed in beds with 

 the common granite ^f; and in the UralUm mountains Her- 

 man observed it mixed with the common granite **. Patrin, 

 who found it in Siberia with the topaz, conjectures that it 



" * Some travellers are of opinion that the serpentine and marble form great 

 feins, rather than vertical strata." 

 " f 4 Bed. Beobacht. 353." 



" J Charpentier M'meralogische Geographe von Chursachsichen Laude." 

 N.Nord. Beytrage. 149." 

 ^ Jour, de Physique. Ann. 1791. 

 ^ N. Bergmanniske'j .Journal, B. 2. 443. 

 ** Herman Mineralcgische Bcschreibung des Uraiaischen Giburges. B. 1 . 1 44. 



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