VEINSTONES. 



pebbles, of various sizes, either round or oblong ; 

 the greatest number being of quartz, like those 

 found on the shores of the sea, and in the beds of 

 rivers ; while the intervals are filled with a white 

 earth, sometimes ochry. The works are 500 feet 

 under the mountain, and the inclination of the 

 vein is from 60 to 70 degrees. Duhamel adds, 

 that the disposition of the vein admits no doubt 

 that it has been formed after the banks of pebbles, 

 which serve it as walls : and that it may be in- 

 ferred that the two banks of pebbles were at first 

 united, and afterwards rent and filled with this 

 vein. But may it not be simply a pudding-stone, 

 of which the cement is decomposed, a common 

 effect of metallic veins* ? Nor is it wholly incon- 

 ceivable that the vast receptacle of subterranean 

 waters, known to exist in many parts of the globe, 

 may contain extensive beds of pebbles, which 

 may be forced into any cavities by the prodigious 

 power of earthquakes, or other phenomena, occa- 

 sioned by the extreme force of steam, vapours, 

 and gases. 



Among the most remarkable veinstones must Petrifaction*, 

 also be classed petrifactions, which have unex- 



* Daub. Theorie de Werner, 83. Near Greenock in Scotland, 

 ore is found in pudding-stone. Will. i. 3*8. 



