AMERICAN INDUSTRIES SINCE COLUMBUS. 319 



out and cut into small rods ; and in Germany and England there 

 is similar machinery, constructed as shown in Fig. 19, which viv- 

 idly represents the whole operation. 



" The furnace shown is simply constructed, and is divided into 

 two parts, beneath each of which is an ash-pit. The iron is 

 thrown into the furnace upon the mineral coal {carbones fossiles) 

 and the bars are placed across one another obliquely, so that the 

 flame and heat will have access to all sides of them. The roof of 

 the furnace is formed into an arch. When the pieces of iron are 

 heated by the direct action of the coal, and by the heat reverber- 

 ated from the roof of the furnace, they are removed and run 

 through two steel rolls." 



By comparing this mill and furnace with those illustrated in 

 Figs. 17 and 18, it will be evident that in the thirty-one years 

 which intervened between the publication of De Ferro and Re- 

 cueil de Planches sur les Sciences et les Arts important progress 

 had been made in the construction of both mills and furnaces. 



We have been thus particular in explaining the construction 

 of the early European slitting-mills because it is certain that 

 many of the ideas embodied in the first American slitting-mill 

 were derived therefrom. 



Industrial history is indebted to William H. Harrison, of 

 Braintree, Mass., for the preservation of a record of the details 

 of construction of certainly one of the earliest, if not actually the 

 first, rolling and slitting mills built in America.* The general 

 plan and elevation of the machinery, as also of the furnace em- 

 ployed in this mill, are shown in Fig. 20, and it will be noted that 

 the natural tendency of the American mechanician to improve on 

 what had already been accomplished asserted itself in this case. 

 The designer while retaining many features of previous mills 

 such as wooden gearing, the use of two under-shot water- wheels, 

 one of which drove the top set of cutters and the bottom roll, 

 while the other drove the bottom set of cutters and the top roll 

 yet made some important improvements in the rolls by increasing 

 their length and making offsets in them f by which iron of vary- 

 ing thickness could be made without changing their adjustment ; 

 and he also "chilled" one end of the rolls. % The furnace was a 

 marked improvement over any before described, and was quite 

 similar in idea to many in use at the present day ; it had a " fire- 

 box" (in which "pine sticks" were used as fuel), a "heating- 

 chamber," and a " chimney." This mill was erected " at Middle- 



* The First Rolling-Mill in America. A Paper read by William H. Harrison, M. E., at 

 the Hartford Meeting of the American Society of Mechanical Engineers, May 4, 1881. 



f A very close approximation to the " grooved roll." 



\ This is believed to be, if not the first " chilled roll " made, yet the first mentioned in 

 rolling-mill construction. 



