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thrown up 2 fathoms by a copper Iptle, and 2 fathoms 

 more by another tin lode; pi. 25, fig. 1. 



In an old mine called Huel Dreath, the back or top 

 of the tin lode appeared three times at the surface, by 

 being thrown up twice on meeting wdth copper lodes, as 

 exhibited in fig. 6, pi. 25. 



In Huel Trevanaunce the tin lodes underlie 10 feet 

 per fathom north, and the copper lodes 3 feet in the 

 same direction; on their intersecting the tin lodes, the 

 latter are thrown down nearly 5 feet. In this mine there 

 is a junction of tin lodes all underlying north, as shown 

 in fig. 5, pi. 25. 



Tin lodes are traversed by cross courses. The shifts 

 of lodes by cross courses and cross flukans, are of course 

 always longitudinal or oblique. At Huel Vor, there are 

 three cross courses which affect the lode in a different 

 way. For several fathoms on each side of the western 

 cross course, the lode is divided into small and almost 

 worthless branches. The middle cross course heaves 

 the lode 27 feet to the right. By the eastern cross 

 course, the lode, at the depth of 20 fathoms, is heaved 

 42 feet to the right, but at the depth of 60 fathoms only 

 6 feet. 



In the north Sealhole mine, the tin lode is heaved 6 

 feet to the right, whilst a neighbouring copper lode is 

 heaved by the same cross course 16 feet; fig. 8, pi. 25. 



The copper lode is intersected at a larger angle than 

 the tin lode. 



Tin lodes are intersected by cross flukans which are 

 observable at various mines. At Huel Vor, there is a 

 cross flukan about 15 feet from the middle cross course. 

 The lode was much richer between the flukan and the 

 cross course, than before it came in contact with either. 



They are also intersected by slides as at Huel Peever ; 

 fig. 2, pi. 25. 



A fine vein of tin lodes of both classes, and of their 



