49 Analyses of Books. [July, 



minerals have also been found in it ; viz. axinite^ garnet, topaz, 

 &c. Are not these some of the strongest marks of a primitive 

 rock? Some specimens of it were sent by a member of our 

 Society to Werner, who recognized in them the clayslate of 

 Saxony. 



" " That grey wacke exists, and abounds in some parts of Corn- 

 wall, will not be denied ; but 1 apprehend it is not to be found, 

 except in small and scattered portions, in that part in which 

 nearly all the tin and copper mines are wrought. It appears to 

 commence near Grampound, and to extend westward about 

 three miles from Truro : how far southward, I have not been able 

 to ascertain. Its extent northward in mass is probably not 

 from Truro ; but it is found in bunches as far as Padstow, and 

 Tintagel Castle. Near the former place, it is highly characte- 

 rized ; and at Tintagel impressions have been found in it. The 

 lead veins of the Garres, and those of Pentire Glaze, and the 

 vein of antimony at Huel Boys, are probably in greywacke ; but 

 I have never seen either copper or tin in greywacke, nor am I 

 aware of any tin veins which intersect it." 



VI. Observations on the Submersion of Part of the MounVs 

 JBay, and on the Inundation of Marine Sand on the north Coast of 

 jCornwall, By Henry Boase, Esq. Treasurer GSC. 



' In this paper, Mr. Boase first examines and refutes the tradi- 

 tion handed down by the historians of Cornwall, respecting the 

 submersion of the country called Lionnesse : he then discusses 

 that which relates to an irruption of the sea over a tract of low 

 woodland, now forming the northern part of the Mount's Bay, 

 showing that it is strongly corroborated by the geological indi- 

 cations of the district ; and he concludes with an account of the 

 overwhelming at an unknown period, by an immense inundation 

 of sea-sand, of a considerable tract of cultivated land on the 

 northern coast of the county. 



VII. On the Nomenclature of the Cornish Rocks. By John 

 Hawkins, Esq. FRS. &c. Hon. MGSC. 



This communication commences with some remarks on the 

 benefits conferred by Werner on the sciences of geology and 

 mineralogy, which are succeeded by observations on the use of 

 the term greywacke, in which the author suggests that the sub- 

 stance so denominated should be considered only as a subordi- 

 nate formation to clayslate. 



The characteristic appellations given by Werner to some of 

 the specimens in a collection of the principal Cornish rocks, 

 transmitted to him by Mr. Hawkins, form the next subjects of 

 the paper, and it terminates with some reflections arising from 

 the consideration of them. 



VIII. On the Temperature of Mines. By John Forbes, MD. 

 Hon. Mem. and late Sec. GSC. 



IX. Observations on the Hornblende Formationin the Parish of 

 St. Cicre. By the Rev. John Rogers, MGSC. 



