Tunnel of the Tavistock Canal. 153 



commencement of the work at the north end, should be one of 

 that description. It is called Wheal Crcbor lode, and has already- 

 been worked about 60 fathoms deep under the level of the tunnel, 

 and has produced between 8 and 9000 tons of copper ore ; its 

 direction is as usual from north-east to south-west, and it has been 

 traced to be the same vein that is worked at Wheal Crowndale mine 

 to the east, in killas ; and at Gunnis Lake mine to the west in granite; 

 at both of which concerns very large quantities of ore have been 

 raised. The lode at Wheal Crebor is in some places fourteen feet 

 wide, though in others not as many inches. It is traversed by cross 

 veins which heave the lode, as the miners call it, a few feet. 



The mine is now producing near 4000 tons of ore in the year : 

 a specimen will be found with the others. 



The next lode found in following the course of the tunnel south- 

 wards contained tin, but not in any great quantity, and very little 

 work has been done upon it in the way of trial in consequence. 



Further south is a lode called Wheal Georgiana, which has pro- 

 duced some rich copper ore in the porphyry, where the tunnel 

 discovered it. It has been pursued into the killas, but in this rock 

 it appears to be less productive of metal. 



At the present end of this part of the work which is approaching 

 the centre of the hill, a vein has just been met with holding cop- 

 per, but too little is yet known of it to afford any description.* 



In the space yet unopened between Brays shaft and the end 

 approaching it from the south, is a lode called Holming Bram, 

 which was formerly worked for tin, and on which considerable 

 expectation is grounded. Having simply stated the facts as far as 

 my knowledge of them goes, I abstain from speculating on the 



* This vein underlies to the south, and is mentioned in a preceding note as an exception 

 to the usual dip of the lodes on this side of the hill. 



