102 ; REPORT—1846. 
Fahrenheit ; the raising of it to 600° before admission to the furnace was 
nothing, nor did it destroy any of its elementary qualities ; it only secured 
its admission and ensured its regularity of action in the process of reduction. 
This was an increase of man’s power over elementary matter: it is by the 
additions to and the increase of this power that men will in time accomplish 
a greater and more powerful condition.” 
The disinclination to adopt an innovation, which as we have seen in this 
case of the hot-blast, has not been entirely overcome by more than fifteen 
years’ experience of its advantages, has not been confined to that instance, 
but has been allowed for a much longer period to influence, in another case, 
the proceedings of our iron-masters. It was as long ago as 1801, that Mr. 
David Mushet, to whom the world is greatly indebted for his scientific re- 
searches and his practical exertions in this important branch of metallurgy, 
discovered when crossing the river Calder, in the parish of Old Monkland, a 
description of ironstone, to which the name of black-band, or Mushet-stone, 
has been given. For many years following this discovery the black-band was 
used only in the Calder Iron Works, which were established in 1800 by Mr. 
Mushet, and it was not even there employed alone, but was used in combi- 
nation with other iron ores of the argillaceous class. It was not until 1825 
that it was first used alone by the Monkland Company, whose success in the 
experiment led gradually to its adoption by other establishments, and to the 
erection of additional works. 
Mr. Mushet, in his ‘ Papers on Iron and Steel,’ p. 128, thus describes the 
advantages of this kind of ironstone :— 
“Instead of 20, 25 or 30 ewt. of limestone formerly used to make a ton of 
iron, the black-band now requires only 6, 7 or 8 cwt. to the production of a 
ton. This arises from the extreme richness of the ore when roasted, and 
from the small quantity of earthy matter it contains, which renders the ope- 
ration of smelting the black-band with hot-blast more like the melting of 
iron than the smelting of an ore. When properly roasted, its richness ranges 
from 60 to 70 per cent., so that little more than a ton and a half is required 
to make a ton of pig-iron; and as one ton of coal will smelt one ton of 
roasted ore, it is evident that when the black-band is used alone, 35 ewt. of 
raw coal will suffice to the production of one ton of good gray pig-iron.” 
This calculation is strongly corroborated by a statement which was pro- 
duced by Dr. Watt to the Statistical Section of the Association at Cambridge, 
from which it appeared, that to make 400,400 tons of iron in the counties of 
Lanark, Ayr, Stirling and Clackmannan, the quantity of coal consumed was 
934,266 tons, or 2 tons 6 ewt. 2 qrs. 18 lbs. for each ton of iron, part of which 
is the produce of argillaceous ores. 
The statement of these discoveries appears necessary in order to account 
for the great and rapid extension given since 1830 to the production of iron 
in this kingdom, and especially in Scotland. 
In 1836 every iron-work in Great Britain was visited, and an account taken 
of its produce, by a highly-gifted gentleman, M. F. Le Play, “ Ingénieur en 
chef,” employed in the Ministry of* Public Works at Paris, under whose di- 
rection are made the yearly reports describing the progress of mining indus- 
try in France, of which I have on former occasions availed myself in pre-- 
paring papers read before this Section of the Association. The result of his 
inquiries showed that in that year the quantity of iron made reached to 
1,000,000 tons, an amount then deemed almost incredible, but which in the 
years immediately following was greatly exceeded. In his ‘ Papers on Iron 
and Steel,’ to which reference has already been had, Mr. Mushet states 
(p- 421) that the quantity of British iron made in 1839, was 1,248,781 tons 
(See App. No. 6). 
