214 September 1749. 



There are fometimes fmall pieces of a 

 greyhli quartz in this fpar, which emit 

 ftrong fparks of fire, when (truck with a 

 fteel. In thefe kinds of ftone the lead .ore 

 is lodged. It commonly lies in little lumps 

 of the iize of peas j but fometimes in 

 fpecks of an inch fquare, or bigger. The 

 ore js very clear, and lies in little cubes *. 

 It is generally very poor, a few places ex- 

 cepted. The veins of foft fpar, and other 

 Jcinds of ftone, are very narrow, and com- 

 monly from ten to fifteen inches broad. 

 In a few places they are twenty inches 

 broad ; and in one iingle place twenty- 

 two and a half. The brook which inter- 

 fe&s the mountain towards the mills, runs 

 down fo deep into the mountain, that the 

 diftance from the fummit of the hill, to 

 the bottom of the brook, is near twelve 

 yards. Here I examined the veins, and 

 found that, they always keep the fame 

 breadth, not encreafing near the bottom of 

 the brook; and likewife, that they arena 

 richer below, than at the top. From hence 

 it may be eafily concluded, that it is not 

 worth while finking mines here. Of thefe 

 yeins there are three or four in this neigh- 

 bourhood, at fome diftance from each other, 



* It is a cubic lead ore, or had glance. Former's Tntrod. 

 fo Mineralogy, p. 5}. 



but 



