420 PHILOSOPHICAL TRANSACTIONS. [anNO l677-8. 



tons, placed on the axis of a very large wheel, which is turned about by water, 

 in the manner of an overshot- wheel. As soon as these buttons are slid off, the 

 bellows are raised again by the counterpoise of weights; by which they are made 

 to play alternately, the one giving its blast all the time the other is rising. 



At first the furnaces are filled with ore and cinder, intermixed with fuel, 

 which in these works is always of charcoal ; laying them hollow at the bottom, 

 that they may more easily take fire : but after they are once kindled, the mate- 

 rials run together into a hard cake or lump, which is sustained by the shape of 

 the furnace, and through this the metal as it melts, trickles down into the re- 

 ceivers, which are placed at the bottom, where there is a passage open, at 

 which they take away the scum and dross, and let out the metal as they see 

 occasion. — Before the mouth of the furnace lies a great bed of sand, in which 

 are made furrows of the shape into which they intend to cast the iron. Into 

 these when the receivers are full they let in the metal ; which is made so very 

 fluid by the violence of the fire, that it not only runs to a considerable distance, 

 but continues boiling for a good while. 



After these furnaces are once at work, they keep them constantly employed 

 for many months together, never suffering the fire to slacken night nor day ; 

 but still supplying the waste of the fuel and other materials with fresh, poured in 

 at the top. 



Several attempts have been made to introduce the use of sea-coal in these 

 works, instead of charcoal ; the former being to be had at an easier rate than 

 the latter; but hitherto they have proved ineffectual. The workmen finding by 

 experience, that a sea-coal fire how vehement soever, will not penetrate the 

 most fixed parts of the ore, and so leaving much of the metal unmelted. 



From these furnaces they bring their sows and pigs of iron, as they call them, 

 to their forges. These are of two sorts, though standing together under the 

 same roof: one they call their finery, the other the chafery. Both of them are 

 open hearths, on which they place great heaps of sea-coaj, and behind them 

 bellows, like to those of the furnaces, but not near so large. Into the finery 

 they first put the pigs of iron, placing three or four of them together behind the 

 fire, with a little of one end thrust into it. Where softening by degrees they 

 stir and work them with long bars of iron, till the metal runs together into a 

 round mass or lump, which they call a half-bloom. This they take out, and 

 giving it a few strokes with their sledges, they carry it to a great weighty ham- 

 mer, which is raised by the motion of a water-wheel, where applying it dexte- 

 rously under the blows, they presently have it beaten out into a thick short 

 square. This they put into the finery again, and heating it red hot, they work 

 it out under the same hammer, till it comes into the shape of a bar in the 



