TRANSITION KQCKS. 137 



i. 29. Vein-stone of Quartz, impregnated vvitli red Oxide of Iron, 



and containing white Steatite, from Tincroft. 

 3o. From the high-road near Tinci'oft. This is a very tough xock, 

 and very fine-grained : it appears to he a variety of Green- 

 stone simihir to NO. 10. 

 31- Killas, marked with dark-coloured spots, from the side of .the 



road to Cambourn, a httle westward of the last. 

 ^^- Killas of a light-grey colour, from St Anns. 

 33. From Beacon Hill, a conglomerate formed of the debris of 

 Granite, very similar to some varieties of Sandstone. 

 Granite from the Land's End. 



Hornblend-Rock from Botallock, a curious, little, but valuable 

 mine, on the north side of the Peninsula, near the ex- 

 tremity. 

 Cockle, massive Tourmaline, from the same place. 

 Specimens from the junction of the Granite and Killas, at St 

 Michael's Mount. 

 . 43. From the shore near Penzance : these I consider to be Ivillas 

 of a very tough and compact variety, they are found verv 

 near Granite, or some similar rock, which presented some- 

 thing so peculiar in the aspect, that I cannot help recom- 

 mending it to the attention of geologists. 

 - 46. Serpentines from the Lizard. 



47. Hornblend-Rock, which forms the basis on which the liffht- 



houses of the Lizard stand. 



48. Clay-porphyry, near Trewithin. 



*9- Granite, with a vein of Tin, St Stephen's. 



SO. Conglomerate of Quartz and Granidar Talc, from the same 



place. 

 *^- Phosphate of Lime and crystallised Talc, in Granular Talc, 



from Stoney Gwins. 

 *3. Killas from a quarry between Bodmin, and the race-course of 



that town. This substance is very soft, hut well adapted 

 Vol. VH. S for 



