54 ‘ SEVENTH REPORT—1837. 
of the same kinds. Under these disadvantageous circumstances, I 
have actually produced from the No. 2 cupola furnace the ton of iron 
in the smelting process, on the average of three months, with less than 
27 cwt. of anthracite coal. The heating of the blast and the calcina- 
tion of the mine require, of course, upon my plan, the same quantity 
of fuel which is necessary for the like processes in other establish- 
ments. 
“With regard to the quantity of iron produced, the result which I 
have to report is equally satisfactory. I must not, however, omit to 
mention, that, for the greater convenience of filling this cupola fur- 
nace, No. 2, from an adjacent gallery, previous to the commencement 
of my anthracite experiment, I raised it in height from 36 feet 6 inches 
to 41 feet. This might have had some effect upon reducing the excess 
of the consumption of fuel when compared with that which had taken 
place in the No. 1, and might have increased its power of smelting 
with my blast of a 14lb. upon the square inch pressure only, from its 
former average of 22 tons to 24. SinceI have adopted the use of 
anthracite coal, combined with hot air, the produce of No. 2 cupola 
furnace, with the same pressure of blast only, has ranged from 30 to 
34 and 36 tons, and one week we actually tapped within 3 ewt. of 39 
tons of grey iron from this furnace. Its present weekly average may 
be expected to range from 35 to 36 tons. 
“ With respect to the quality of the iron produced by the com- 
bination of hot blast and anthracite coal, the result is very satisfactory. 
It is well known in my neighbourhood, that my cold blast iron, for all 
purposes where great strength was required, was never deemed inferior 
toany smelted in South Wales. That which I have hitherto produced 
with hot blast and anthracite coal is, however, decidedly stronger than 
any other before smelted at the Ynyscedwin iron-werks.” 
The anthracite formation probably occupies about one-third of the 
mineral basin of South Wales. It commences near the upper part of 
the Vale of Neath, in the county of Glamorgan, and proceeds in a 
westwardly direction through the remainder of that county; thence 
through Carmarthenshire, and crops out in the sea in St. Bride’s Bay, 
after passing through a considerable portion of the county ef Pem- 
broke. It is likewise to be found in Ireland, Scotland, France, Austria, 
Bohemia, and Sardinia, and very large deposits of it have been already 
discovered on the continent of America, particularly in the state of 
Pennsylvania. 
On Safety Lights for Mines. By Dr. Arnort. 
The writer of this having had his attention called to the objects 
sought to be accomplished by the Davy Lamp, as related to the general 
subject of ventilating and warming, which he has treated elsewhere, 
conceived that perfect security against explosions in mines was ob- 
tainable in a very simple way, but on a principle differing entirely 
from what has directed previous attempts. This is to have the lamps 
