of Silver in Herland Copper Mine. 161 
Lodes in this direction are usually filled with quartz, but 
frequently produce galena; and sometimes, instead of galena, 
sulphurated antimony. They appear here to conform to the 
same laws, except in the particular instance now to be described, 
which forms, indeed, a very remarkable exception. 
No ores of silver were observable in this lode, until at the 
depth of one hundred and ten fathoms from the surface, or 
eighty below the adit or level; and, at the farther depth of 
thirty-two fathoms, they disappeared. 
They have been discovered only in the neighbourhood of 
one of the intersected copper lodes, extending no where above 
twelve feet from this lode, on the north, or above thirty-two feet 
from it, on the south, and acquiring this their greatest extent at 
the deepest level; for, the usual dimensions of the silver ore are 
not more than six feet in the former situation, and twelve feet 
in the latter. 
It is remarkable, that at the point of contact or intersection, 
the contents of the silver lode are so poor as to be scarcely 
worth saving ; and those of the copper lode are much less pro- 
ductive of copper than at a little distance from this point. 
Moreover, that the copper lode, in the vicinity of the intersec- 
tion, seems to have been influenced by the same causes of im- 
provement and declension as the cross lode; being richer or 
poorer in copper, as the latter was, at a correspondent level, ill 
silver. 
The richest mass of silver ore was found at the depth of two 
fathoms above the level at which it disappears. 
After this brief account of the most striking facts, it may be 
proper to enter into a more particular description of the two 
MDCCCI. Y 
