1814.] Northumberland, Durham, &c. 419 



their meaning in the common mineralogical language which has 

 been adopted in this country. Such a list may be of some little 

 sendee to futuie mineralogists : — 



Flats A swelling out of the vein. 



Forehead Extremity of the working of a mine. 



Girdle A thin hard bed of slate-clay or sand-stone. 



Groove* .... A mine. 



Hazle Sand-stone. 



Metal-stone. . Slate-clay. 



Plate Slate-clay. 



Post Sand-stone. 



Rider The upper part of a vein. 



Scarr A rock. 



Shiver Slate-elay approaching to shale. 



Sill A bed. 



Sulphur Iron pyrites. 



Thill Clay. 



Whynn Hard sand-stone or slate-clay. 



These I conceive to be the most striking terms, and the most apt 

 to puzzle strangers. 



Article III. 



Mineralogical Observations. By Professor Jameson. 



A knowledge of the various appearances presented by cotem- 

 poraneous imbedded masses and veins, and of the relations of beds 

 and strata to each other, not only facilitate mineralogical investiga- 

 tions, but also aid u<= in our geognostical speculations. In the 

 lecood volume of the Memoirs of the Wernerian Society 1 have 

 already touched on these subjects ; and I shall now add some facts 

 to those already stated in that work. 



I. — On Cotemporaneous Masses. 

 1 In granite mountains we sometimes observe portions of gneiss, 

 mica-slate, clay slate, and also of porphyry, syenite, and trap, 

 varying in size from a few inches to many fathoms. These masses 

 are to be seen passing by imperceptible shades into the bounding 

 pranite : thus showing that they are of cotemporaneous formation 

 with it, and are not fragments, as has been frequently maintained. 







• Thi. .5 exactly the Swediih word grufvt, which has the iaa>e meaning, an* 

 almvit the tame sound. 



2 P2 



