1854.] 



RAMSAY ON THE GOLD ROCKS OF N. WALES. 



243 



'S. 





09 



s 

 I* 





'^ 



arj 



are four quartz-lodes, bearing a little copper, in a mass of trap that 

 lies on the W. of the road between the third milestone and Tyn-y- 

 groes. One of these at Cae-nant runs E. and W. Three near Tan- 

 'rallt run N. and S. There are two quartz-lodes with lead a little 

 N.E. of Moel Ispri, and at least seven similar lodes yielding a pro- 

 portion of copper on the hills immediately N.W. of the Barmouth 

 road, between Llanelltyd and the fourth milestone from Barmouth. 



The country in which the Dol-y-frwynog mine lies is interesting, 

 and in part peculiar. I shall describe its geology in some detail. 



Immediately north of 

 the third milestone on 

 the Dolgelli and Ffestin- 

 iog road, a mass of very 

 felspathic greenstone, 

 mentioned above, breaks 

 through a low part of the 

 i.-c' / £ Lingula-beds. It occu- 



^ ^. pies the heights on which 



^„ stand the houses of Tan- 

 "' 'rallt and Hafod-y-fedw. 

 It is about amile in length 

 from N. to S., and extends 

 from the road about three- 

 S, quarters of a mile west- 

 ^ ward. Three of the lodes 

 already noticed as yielding 

 copper lie on its eastern 

 slopes ; and I have been 

 informed by my friend 

 Mr. Byers, of Dolgelli, 

 that a very little gold was 



•U3M uojv - 7/ i.i 'III detected in one of them, 



in the year 1836, by Mr. 

 O'Neil. 



For four or five miles 

 N. of this area several 

 other lodes occur in the 



■qoBpp/rtBiM uojv 1^ . Lingula-flags and their 



associated traps, on the 

 banks of the Mawddach 

 and of Afon-wen, The 

 accompanying section ex- 

 plains the geological re- 

 lations of part of this 

 country that lies between 

 Rhobell-fawr and the 

 Cambrian rocks immedi- 

 ately N . of Dol-y-melynen. 

 On the "W. are the Cambrian grits (No. 1), dipping eastward at 

 angles varying from 40° to 60°. These are overlaid conformably by 





