212 [AsSEMBLt 
abandoned, and some have been disappointed in investments. They 
were made in a time of too great excitement, and with too little know- 
lege of the character of the veins. It may be considered as established, 
that a very narrow vein at the surface never will of itself pay for work- 
ing, and that it is not probable that in following it directly downwards, 
it will enlarge into a wide and profitable deposit of lead. It may be 
what is called a leader, that is, conduct the miner along the surface to a 
wider vein. When facts of this kind are well understood, there will be 
no more danger of failure in the mining business, than in any other. 
In the other veins of galena, which have been explored to the great- 
est extent, and which have yielded the most, there is a remarkable free- 
dom from minerals of inferior value, or, the sulphuret of zinc and iron, 
especially the latter. This is a favorable circumstance, and accounts for 
the great softness of the Rossie lead. This increases its value, as it is 
more readily converted into white lead. 
An examination of the country, in the vicinity of Rossie, must satis- 
fy any one that it has the character of a mineral region, and that there 
is much probability that we have but just commenced in the mining bu- 
siness, and that there are many other deposits of lead to reward explo- 
rations. 
Copper. 
The opinion expressed last year, that copper would be added to the 
mineral wealth of St. Lawrence, has been in part realized. Two new 
veins have been discovered which have yielded quite a large supply of 
ore. One of these is about five miles Irom Rossie, beyond Baker's or 
De Long's mills. The other is in Canton, on uncultivated lands owned 
by Mr. Van Rensselaer. 
The course, or direction and geographical position of the former, is 
given on the map of the mining district of Rossie. There is every in- 
dication here of a rich vein. I found that several tons had been raised 
from the mine in searching for a bed of iron. 
The value of copper is so great that it is justifiable to risk a large 
sum in sinking a shaft to ascertain the nature of the vein. 
The sulphuret of copper and iron furnishes, by chemical analysis, 
about 30 per cent of copper. But by intermixture of iron pyrites more 
or less in the vein, it is rare to obtain half that amount of copper by 
smelting in the large way. The following iterr of statistics may be in- 
teresting in relation to the Cornish mine. 
