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ROLLING MILLS 



HOCK SAIiT. See SALT. 



ROE STONE. A name for oolite, from its being like the roe of fish. See OOLITE. 

 ROLLERS, ELASTIC, for printing. See PRINTING HOLLERS. 

 ROLLING MILLS. These useful aids to many of our metallurgical processes 

 appear to have been introduced. to this country in the seventeenth century; but it 



was not until 1784, when Mr. 



1721 Co**- patented 'a new mode 



and art of shingling, welding, 

 and manufacturing iron and 

 steel into bars, plates, &c.,' 

 that much attention was di- 

 rected to the value of the 

 rolling mill. 



Fig. 1721 is a front view 

 of a pair of rollers, used in 

 the manufacture of iron in 

 connection with the puddling 

 furnace. They are about 4 

 feet long, divided into four 

 parts, the largest being about 

 20 inches in diameter. The 

 portion of the upper roller 

 under which the metal is first 

 passed, is cut in a deep and 

 irregular manner, resembling 

 that chiselling in stone called ' mosaiq lie-work,' that it may the more easily get hold of 

 and compress the metal when almost in a fluid state. The plate is next passed under 

 the cross-cut portion of the roller, and successively through the flat sections. The 

 lower roller, it will be observed, is formed with raised collars at intervals, to keep the 

 metal in its proper course. The rollers are connected by cog-wheels placed upon 

 their axes ; upon the lowermost of these, works also the wheel by means of which 

 the revolution is communicated. The cheeks are of cast iron, very massive, that they 

 may bear the violent usage to which they are subjected. 



We cannot go into the numerous purposes to which rolling mills of this kind are 

 applied ; a few may however be mentioned. 



The practice of ' slitting ' sheets of metal into light rods, either for the use of the 

 wire-drawers or of nail-makers, is carried out by means of two large steel rollers, 

 channelled circularly, as in Jiff. 1722. These are so placed that the cutters or raised 

 parts of one roller, which are exactly turned for that purpose, shall work in corre- 

 sponding channels of the other roller, thus forming what may be called revolving 

 shears, for the principle is that of clipping ; so that a sheet of metal on being passed 

 through this machinery, is separated into slips agreeing in size with the divisions of 

 the rollers. 



1722 



1723 



For the manufacture of rails, rolling mills are also employed, fig. 1723 representing 

 a rolling mill as constructed for rolling Birkinshaw's rails. The open spaces along 

 the middle of the figure, and which owe their figure to the moulding on the periphery 

 of the rollers, indicate the form assumed by the iron rail as it is passed successively 

 from the larger to the smaller apertures, till it is finished at the last. 



For a further description, and for the arrangement of rolling mills and slitters, see 

 IRON. Beyond these few notices the character of this Dictionary will not admit of 

 our going ; the reader is therefore referred to the works which have been published 

 on the Metallurgy of Iron and Steel, for further information. 



Rolling mills have been patented for rolling tubes for gas and other purposes. See 

 TUBKS. 



