64 THE SCIENTIFIC PAPERS OP 



A fire having been lighted upon the hearth B through the side 

 opening K, the flame passes through the furnace and through the 

 regenerator E to the chimney Gr. In its passage through the 

 regenerator E, the first perforated wall that the flame strikes 

 against will be heated to a considerable degree, the second wall to 

 a lower degree, and so on in succession, the heat of the current 

 being thoroughly exhausted by the time it reaches the chimney. 



After about one hour's work the position of the valve F is 

 reversed and fuel is supplied through the opening L to the second 

 fireplace C, which is then acted upon by a current proceeding in 

 the opposite direction to that indicated by the arrows. The cold 

 atmospheric air comes in contact first with the least heated wall 

 of the regenerator E, and then with the more heated walls succes- 

 sively, acquiring thereby a degree of temperature approaching the 

 temperature of the heated current which previously entered the 

 same regenerator. The heat thus imparted to the fresh air 

 greatly increases the temperature of the flame which is now being 

 produced upon the hearth C, and consequently the nearest end of 

 the regenerator D will be heated also to an increased degree, the 

 current reaching the chimney comparatively cool. 



When the valve F is again reversed, the fresh air will be heated 

 nearly to the increased temperature of the hot end of the regene- 

 rator D, and will produce a still hotter flame with the fuel supplied 

 to the hearth B. It is evident that by a continuation of this 

 process an accumulation of heat to any degree may be produced 

 within the furnace, provided only the heat produced in combustion 

 is greater than the heat lost by radiation and the heat absorbed by 

 the metal or other substances in the heating chamber. 



In the regenerative furnace now described, the temperature at 

 which the heat is communicated to the materials does not affect 

 the quantity of fuel requisite, except so far as increased radiation 

 is concerned ; for the products of combustion pass away in all 

 cases at a temperature not above 200 or 300 Fahr. This new 

 principle of furnace is therefore applicable with the greatest 

 advantage in cases where intense heat is required. It has been 

 applied to furnaces for reheating steel and iron, at the works of 

 Messrs. Marriott and Atkinson at Sheffield. One of these furnaces 

 has now been in constant work for nearly three months ; and 

 according to a statement received from Mr. Atkinson it has worked 



