ON THE MANUFACTURE OF IRON. 738 
yield of both seams, contained in an acre of ground, Mr. Cargill estimated 
at 5324 tons. In later years, however, according to a detailed report com- 
municated by Mr. Edward T. Boyd, the average produce of the first-men- 
tioned seam, “‘ The Ten Band,” as it was called, at that time was 8 inches 
of ironstone in a working 5 feet 9 inches high, and in the other bed his 
section gives— 
Good conliir.ns. Bie acces steht ete 1 ft. 6 in. 
Pping Own searic aa ery. eeeeaaneaee 0 
2 ft. 1 in. 
PEROMSLOUD cn aicty dass vc.nningstajas ca conaehaastict O 43 
BGM acn eons es ass se sevens sins te aemegeenaace 3 
—_ 3 103 
5 113 
For a limited supply, the quantity of ironstone found in this neighbourhood 
might have sufficed; but an immense work having been erected upon it, 
comprising fourteen blast-furnaces, serious inroads were soon made on its 
resources. From information formerly received, it would not appear, what- 
ever might be the richness of clean stone, that its yield, as delivered to the 
furnaces, exceeded 26 per cent. The cost on a ton of iron, for ironstone, at 
Shotley was 25s. to 30s., which compelled the owners of this establishment to 
look to another district for their supplies, so that at the present time every 
pit on their royalties is laid in. 
A small quantity of ironstone continues to be extracted from a landsale 
colliery at Hedley, which is smelted at Wylam, and, as the writer believes, 
some is still worked by the Weardale Iron Company near Tow Law. Ina 
general sense, however, it may be assumed that ironstone of the coal-forma- 
tion of the North of England forms no element at the present day in the 
consumption of the blast-furnaces of that district. 
The Iron Ores of the Mountain Limestone——Following the order of our 
description of the geology of the country, the deposits of ironstone con- 
nected with the mountain limestone next demand notice. In this series 
there occurs a bed of shale 30 feet in thickness, in the whole of which con- 
siderable quantities of nodules of ironstone are interspersed. The late Mr. 
Thomas J. Taylor, in evidence on the Border Counties’ Railway Bill before 
a Parliamentary Committee in 1854, stated this shale bed to contain 9680 
tons of ironstone to the acre, of which he assumed practically 6000 could be 
obtained. Its cost he stated to be 6s. 6d. to 7s. per ton, and its yield such 
as would require 31 tons of stone to produce one ton of iron, equal to 30°5 
per cent. Mr. Benjamin Thompson, who worked this bed at Hareshaw, in- 
forms the writer that 8470 tons of ironstone per acre was its contents, and 
of this the lowest 6 feet contained two-sevenths of the whole. Allowing 
one-third for loss, he considered 5647 tons as the practical produce of an 
acre. Its yield he gives as 33 per cent., and its cost 9s. per ton of 22} cwt., 
equal to 8s. per ton of 20 cwt. At Ridsdale, from data possessed by the 
writer, the cost of ironstone for a ton of iron was 29s. 3d. This deposit has 
been somewhat extensively wrought at Hareshaw and Ridsdale, as well as 
attempted at other places. In all these localities, however, the workings 
have been discontinued. 
At Chesterwood, about two miles from Haydon Bridge, there was opened 
out, some years ago, a seam of what in some measure resembled the famous 
«“ Black-band ironstone” of Scotland, containing, however, much more coal 
than the celebrated ore of this name. It varied, according to Mr. Bigland, 
who worked it, from 3 to 4 feet in thickness. The raw stone contained 20 
