968 



IRON 



be raised, the full width of tho mouth being retained, and the gases must be withdrawn 

 sufficiently far below tho mouth for them to bo obtained dry, and also beneath the/ 

 point where they begin to enter into combustion from contact with tho atmospheric air. 

 Various modes of collecting tho gases have been tried ; the best seems to bo that 

 adopted at Ebbw Vale, Sirhowy, and Cwm Celyn. A funnel-shaped casting, equal in 

 its largest diameter to tho throat of tho furnace, projects into tho interior a depth of 



3242 



4 or 5 feet ; the orifice at tho bottom, from 3 to 5 feet in diameter, is closed by a conical 

 casting, the apex upwards, from which a chain proceeds to a lever having a counter- 

 poise at the other end. (Scofy. 1241.) Tho materials are filled into tho funnel-shaped 

 receptacle, and are charged into tho furnace with a uniform distribution, by lowering 

 the cone by means of suitable machinery, which again returns it to its place when 



