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boulders from the shore and those in siiA in the clay, and at 

 the same time making ourselves acquainted, as far as we could, 

 with the rocks in situ in the district. We do not pretend, of 

 course, that we have accomplished all this ; we are, indeed, only 

 on the threshold as yet; but so far as we have gone, we have not 

 found amongst all these slates, limestones, granites, and traps, any 

 rock that may not have been derived from the Lake district, with 

 the single exception of what, for convenience we will term — 

 vermiculitic granite. To prove the proximate derivation of the 

 mass of boulders, it was very desirable, if possible, to find any 

 that should possess such marked characteristics that there should 

 be no question as to their origin; we therefore considered the 

 vermiculitic granite as of special value in this respect, though as 

 yet we have not been able to trace it to its parent rock. You will 

 see from the specimens exhibited, that it might easily be mistaken 

 for ordinary granite containing black mica, and it was almost by 

 accident that the curious properties of some of the black crystals 

 were discovered. The mineral was too uncommon and peculiar 

 for us to bring it forward publicly, without having upon it more 

 than local opinion. I sent specimens to the late Mr. David Forbes, 

 and received from him, only a few days before his lamented death 

 last year, a long letter, in which he stated his impressions that the 

 mineral was a vermiculite, but if so, it was previously unknown to 

 Great Britain ; he thought the subject to be of considerable interest, 

 and intended to have continued his investigations. After his death 

 I took other specimens to the British Museum, where nothing was 

 known as to any similar mineral having been discovered in Great 

 Britain. It has now been found in several localities near Barrow, 

 and also by members of our Field Club near Millom and at 

 Nethertown. The granite in which it is contained is usually 

 friable and partially disintegrated, or it may be that unless the 

 granite be in this condition, the vermiculite is not so easily 

 recognized. Possibly the Ennerdale district may be the home of 

 this rock, yet if so, it is strange that the vermiculite has not been 

 detected in sitA by some of your Cumberland savants ; but if this 

 assumption as to locality be correct, I trust another summer will 



