196 



from the Caldbeck Fells. A chromiferous variety is occasionally 

 found in the Caldbeck Fells. 



MiMETisiTE, MiMETiTE, Kampylite, the Lead Arseno-phosphate, 

 occurs chiefly at Dry Gill, a short distance to the east of Rowtin 

 Gill. It is associated, on the vein-quartz of that part, with Pyrolu- 

 site, and other ores of Manganese, and it occurs in the form of small 

 barrel-shaped aggregations of crystals, which present a cross-section 

 of an hexagonal form. The staves of the barrel, if one may so 

 speak of them, are usually as smooth and bright as if they each 

 really represent a single veritable face of crystallization, notwith- 

 standing that the faces of the staves are considerably curved. This 

 is another point connected with the minerals of our district that 

 yet requires to be worked out. Another point in connection with 

 the same mineral is, why it should be present in one particular 

 vein where there are no traces of other compounds of either Arsenic 

 or Phosphorus, while in an adjoining vein where Arsenates, Phos- 

 phates, and ores of lead are decomposing in the same vein, this 

 particular mineral should be rare or entirely absent. 



