in Herland Copper Mine. 79 



pafs ; the crofs lode nearly north and fouth, or at right angles 

 to it. 



The former is about two feet broad, on an average; and 

 it dips or underlies fouth, one foot in a fathom. The 

 breadth of the latter is about two feet and a half, on an ave- 

 rage; and its underlie is eaft, about eight inches in a fathom. 



The heave of the copper lode is about eighteen or twenty 

 inches to the right, in the language of the Corniih miner ; 

 the expreflion being fo far appropriate and convenient, as it 

 refers to the ulual iitua.tion of theobferver in the heaved lode. 



The copper lode is filled with layers of ore and ftony mat- 

 ter, the latter of which is here called caple\ but the ore is 

 ufually found contiguous to the walls of the lode. 



The contents of the crofs lode are more lingular, in refpecl; 

 to their local position, and more various. Only the eaftem 

 fide of it produces filver ore, the breadth of which is in ge- 

 neral about fix or eight inches, although in fome places it is 

 greater. The other part of the lode is chiefly compofed of 

 quartz, intermixed with iron, manganefe, and wolfram, to- 

 gether with a fmall portion of cobalt and antimony. 



The filver ore, ftrictly f peaking, is a mixture of galena, 

 native bifmuth, gray cobalt ore, vitreous filver ore, and na- 

 tive filver; which, in refpecl: to their proportions, follow the 

 order in which they are here enumerated, the galena being 

 the mod prevalent. The native filver, of which fpecimens of 

 the greater! beauty have been referved for the cabinets of the 

 curious, is found chiefly in a capillary form, in the natural 

 cavities of the lode. 



About one hundred and eight tons of this ore have been 

 raifed. The miners continue to fink near the fame point of 

 interferon ; and feem confident that both lodes will foon 

 become richer, becaufe fimilar initances of declenfion and 

 recovery have frequently occurred in the copper lodes of this 

 mine, and becaufe the two lodes appear to have a reciprocal 

 influence on each other. 



Unfortunately, however, the extent of their fpeculation h 

 limited by the great depth of the prefent workings; for, 

 fortv-fivc fithoms have been funk fince the firfi. difcovcry of 

 the filver; and twenty, or twenty-five fathoms more, are as 

 much as can be funk in this mine, with its prefent mecha- 

 nical powers of drawing the water; at which level, viz. one 

 hundred and eighty tathoms from the furface, it would be 

 fomevv hat deeper than any mine in Cornwall, and about one 

 hundred and thirty fathoms below the level of the fea at low 

 water mark. 



The other crofs lodes in this mine produce no filver ; mod 



of 



