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diffused throughout a considerable thickness of the associated 

 rocks above. This view is quite compatible with the theory 

 regarding the origin of gypseous deposits advanced by Sterry Hunt, 

 and advocated by Sir Andrew Ramsay and others, namely, that 

 most of them represent deposits accumulated in great inland 

 lakes. 



The preservation of our beds of gypsum is, I think, largely due 

 to the fact that they occur in the midst of what are practically 

 water-tight strata. The gypsum in almost any quarry one may 

 examine is manifestly disappearing so fast under the dissolving 

 influence ot surface waters that it may be matter for wonder how 

 any of it has been preserved so near the surface at all. The explan- 

 ation I believe to be the true one is that all the portions of the 

 strata that had had their gypsum carried away in solution before the 

 Glacial Period were cleared off the face of the country along with 

 other weathered rock when the great ice-sheet swept the district 

 from end to end. It was to this same cause, as I have elsewhere 

 shewn,* that all the preglacially-weathered limestone of the Carbon- 

 iferous areas owes its removal. The rock was scraped off down to 

 where sound-and unweathered stone occurred, and it is at this 

 point that the action of the weather is just beginning again to 

 reassert its sway. 



In connection with the origin of gypsum we have yet to leam 

 whether its initial stage was that of Anhydrite, or whether Anhydrite ' 

 represents a dehydrated form of the commoner mineral. 



Occasionally, beautifully lustrous, and satiny, deposits of fibrous 

 gypsum occur. One such may be well examined in the south 

 bank of the Eden at Windanwath. Specimens from this locality 

 are exhibited in the county Museum at Carlisle. 



Gypsum occurs in the Upper Red Shales or Stanwix Marls as 

 well : probably, as it usually does on this horizon, in association 

 with Salt. 



None of the Chromates seem yet to have been recorded from 

 Cumberland and Westmorland localities. 



One of the rare minerals occurring at RowtinGill is Brochantite. 

 * Geological Magazine, article on "Glacial Erosion." 



