88 Mr. N. J. Winch on the Geology of 



In small lancet-shaped crystals, opake and white, occasion- 

 ally aggregated into a cellular mass ; from Arkendale. 

 In transparent tabular bevelled crystals. Those from 



Dufton are very fine. 

 Of a milk white colour, not bevelled, set edgewise on 



quartz, blende, and galena ; from Aldstone. 

 In 4-sided transparent prismatic crystals, acuminated by 

 2 planes set on the lateral planes j from a vein at Dukes- 

 field. 

 A curious mineral is found in some of the Aldstone moor veins. 

 It consists chiefly of indurated clay with a mixture of iron ; is of a 

 smoke-grey colour, very hard and sonorous, and is intersected by 

 deep impressions of tabular crystals of heavy spar, which have in 

 some unknown manner been decomposed. 



Earthy Minerals. 



Qtiartz. — Is found crystallized in 6-sided pyramids in most of the 



mines. 

 Asbestus. — Of a leek green colour, has been observed by Mr. Bigge 



in Melmerby scar, forming veins in a hard reddish brown 



rock resembling basalt, but not magnetic. 



I am not informed of more than six mineral springs in the district 

 of the lead-mine measures, and of these only two have attained any 

 degree of celebrity. These are the springs of Gil-land and Wardrew, 

 which were analyzed in 1799 by the late Dr. Garnet. The sulphu- 

 retted water issues from a thick bed comprising 3 distinct strata of 

 shale, which is covered by several measures of sandstone, forming 

 together a perpendicular cliff about 90 feet in height on the north 

 bank of the little river Irthing. Two gallons and a half of water 



