Exam'uu-.tion of Steel. jif 



hufbandry, common cutlery, and fprings. As this kind of Red demands lefs expence ia 

 its fabrication, it is of courfe the cheapeft. The greateft quantity is imported (into France) 

 from Germany. 



2. The fecoiid kind is fteel of cementation. It prefents a more equal grain in its frac- 

 ture, and takes a better polifh than the former. It is alfo harder, more brittle, and requires 

 more particular attention in the forging. This kind being more perfeft, is of great ufc in 

 all the circumftances which require the qualities here mentioned. 



3. LaRly, the third kind is caft-fteel, obtained by fufion of 07ie of the other of the fore- 

 going kinds. It is charaaerifed by its uniformity of texture, and is deprived of thofe fca- 

 brous places which are obfervable even in the fteel of cementation. This third kind of 

 fteel is therefore fufceptible of the moft beautiful polilh, and is proper to form razors, Ian- 

 cets, ornamental work, wire-plates, laminating rollers, &c. The Englifh have hitherto 

 been almoft totally in poflelTion of the manufaaory of caft-fteel, which is the moft valuable 

 of any. 



Four bars of cemented fteel, manufaaured by Mr. Soller, and chofen from among the 

 fteels of different qualities in his warehoufe at Paris, were fubmitted to the following ex- 

 periments : 



With the firft piece fome hook-tools* for turning iron were made. They forged very 

 xvell, the fteel being very hard in the fire, and confequently eafy to be wrought. The hook- 

 tools, on trial, proved very good. A graver for turning iron in the turn-bench was made 

 out of the fame piece. It was tried upon fteel, and found to be as good as an Englifli 

 graver. 



The fecond piece was ufed to make a plane iron for metal. It fucceeded perfeaiy well, 

 and kept its edge in planing iron as long as thofe which are "made of Englifh fteel. 



Out of the third piece, which was doubled into three, and welded upon apiece of iron, 

 3 carpenter's chifel was made 26 lines in breadth. The fteel welded perfeaiy, without re- 

 quiring any particular care. The edge proved very good, and on comparifon with an 

 Englifli chifel of the fame dimenfions it was found to poffefs the fame qualities. 



A carpenter's chifel, 1 4 lines broad, was made out of the fourth piece of fteel. It welded 

 extremely well, and proved to be as good as the foregoing inftrument. The workmen eftimate 

 that a greater number of EngliOi chifels would be found at the venders' below than above 

 this quality. 



Mr. Soller likewife fent to the commifTioncrs a fample of iron, which was part of the tie 



• The hook-tool is ufcd by the turners of ftrong metallic work ; but from its fleadinefs, and other good qua- 

 lities, it well dtferves to be applied in many delicate operations with fteel and brafs, by a numerous fet of wurk- 

 men in this capital who are entirely unac<iuaint£d with it. Its ufual form is that of a hook or claw, Itfi than 

 half an inch long, proceeding nearly at right angles from the fide of a ftraight ftcm, which Idft terminates below 

 in a point. The culling edge is at the cxiremiiy of the claw, and is varioully figured, aca.rding to the nature 

 of the work. By bearing the angular point on the Reft uf the lathe, ihc claw may be applied to the work wiih 

 great power and fleadinefs, while the perpendicular handle hears againft the flioulder of ihc w orkman. The 

 flcel commonly ufcd in London for this inftrument is called flieer-ftecl, from its mark The edge ftands very 

 well agtiihft foft fteel, when the tool is a little liardcr than a hard fuv, or juft cap:.ble of yielding to a good 

 I.ancaQure file. If it be harder, there is a greater probabiliiy of its breaking. This kind of work is performed 

 by a flow motion, with the conflant application of water to the piece to prevent heatin£. It is obvious from 

 thefc liiU that tenacity is the reciuifite moft wanted here. N. 



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