ON THE LOCAL MANUFACTURE OF LEAD, ETC. 715 
On the Local Manufacture of Lead, Copper, Zinc, Antimony, &c. 
By T. Sorwitn, F.R.S., and T. Ricuarpson, M.A., F.R.S.E., &c. 
Leap. 
Tue lead-mining districts of the North of England are chiefly situated in or 
near the centre of that narrow portion of Great Britain which is formed by 
the counties of Northumberland, Durham, Cumberland, and Westmoreland, 
and may be considered as being nearly in the central portion of the whole 
island, being situated nearly midway in its length from north to south, 
as well as from east to west, between the German Ocean and the Irish Chan- 
nel, Under the level lands which lie near to the eastern and western coasts, 
the upper portion of the carboniferous series of rocks contains numerous and 
valuable beds of coal. From beneath these coal-strata the “ lead-measures,”’ 
as they are locally termed, that is to say, the several beds of limestone and 
other rocks in which veins of lead-ore are chiefly found, gradually rise in a 
westerly direction, with an inclination exceeding that of the general rise of 
the surface, until they basset or crop out at the surface over a wide range of 
country, reaching their highest elevation at the mountain of Cross Fell in 
Cumberland, and other adjacent fells or mountain moorlands which extend in 
a north and south direction so as to form a western limit to the lead-mining 
districts. The strata which extend between the outcrop of the lowest of 
the coal-strata and the Cross Fell ridge of mountains are well known in 
the district as the carboniferous or mountain-limestone formation—so called 
from the abundance of coal so nearly associated with them, and from the 
numerous beds of limestone which prevail. These lead-mining strata lie 
nearly midway in the series of formations which are known in England, 
being as much below the tertiary beds of the south-east part of the island 
as they are above the Silurian rocks on the borders of Wales. A lofty range 
of elevated land extends from the borders of Scotland to Derbyshire, occupy- 
ing from twenty to thirty miles in width of the middle portion of the north 
of England. In many parts of this range of hills are extensive lead-mines, 
which may be classed as follows :— 
1st. Mining districts connected with the river Tyne and its tributaries— 
the Nent, East and West Allen, and the Derwent; Alston Moor, in the 
county of Cumberland; East and West Allendale, in the county of Northum- 
berland; Blanchland, and Derwent Valley, in the same county. In addi- 
tion to these, which form, as it were, distinct mining territories of consider- 
able extent, other valuable mines in detached places have been discovered, 
and are extensively worked in the valley of the Tyne. 2nd. The extensive 
mining districts of Weardale, in the upper part of the valley of the river 
Wear, and its tributary valleys of Burnhope, Kilhope, Wellhope, Ireshope, 
Rookhope, &e. 3rd. Another extensive district in Teesdale, in the upper 
part of the valley of the river Tees, the mines being situated chiefly in 
the county of Durham, and partly in Yorkshire, worked by the London Lead 
- Company. 
The geographical position of these districts may be readily understood by 
referring to ordinary maps of this part of England, and by assigning to the 
upper part of the rivers Tyne, Allen, Wear, and Tees an area extending about 
twenty miles from their respective sources, and in the Derwent a range of 
about ten miles from its source. This would roughly indicate the position 
of the principal mines. 
Tn any view of the history of mining it is impossible to overlook its con- 
nexion with geological conditions on which the very existence of the mine 
