283 l^lPPEIirMENTS 



portion firft rendered fluid, to receive their proportion of the 

 fleely principle. Where Ihe heat is languid, the defcent oF the 

 lafl portions of iron is fluggifli, the mafs below begins to lofe 

 its fluidity, while its diCpofition for giving out carbon is reduced 

 by the gradual addition of more iron. An accumulation takes 

 place of metallic maifes of various diameters, rifing up for 

 half an incH'^r mor^ into the glafs that covers the metal ; 

 thefe ar© neatly welded and inferted into each other, and 

 diminini in diiffnet'er afs'they go up. ** 'The length, 6r even the 

 exiflence of thii< feeder 6r excrefcence, dep'ends upon the heat 

 in genieral, and upon its temperature at different periods of the 

 fame pl-ocefs. If there has- been fufficient heat, the furface 

 will be convex and uniformly cryftalline ; but if the heat has 

 ^eeti urged, after the feeder has been formed and an affinity 

 ■eftftblidied between it and the fleelifted mafs below, it will 

 only partially difappear in the latter, and the head or part of 

 ' ' the upper end of the feeder will be found fufpended in the 



il fli. gJa^s ^i^^t covers the tieel. 



The fame or fimilar phenomena take place in feparating 

 crude iron from its ores, when highly carbonated', and dif- 

 ficult, from an excefs of carbon, of being fufed. 

 • Tlie divifion of the woo?z cake by the manufa£iurers of 

 Hindoflan, I apprehend is merely to facilitate its fubfequent 

 application to the pnrpofes of the artifi ; it may ferve at the 

 fame time as a teft of the quality of the fteel. 

 Experiments to To afcertain, by direiSl experiment, whether woofz owed its 

 afcertain the hardncfs to an extra quantity of carbon, the following expe- 

 meafarc cf riments were performed with various portions of wootz of 



carbon in wootx, common caft fteel, and of white crud6 iron, premifing that 

 y t e quantity j opej-a^JQ^g vvith iron and its ores, I have always found the 



or lead it reduces . • ' •/ 



from flint glafs. Comparative meafure of carbon befl: afcertained by the quan- 

 tity .of lead which was reduced from flint glafs. 



IJl Cake. Grains, 



Fragments of wootz . - ... 65 

 Pounded flint glafs three tinges the weight - 195 



This mixture was expofed to a heat of 160® Wedgwood^ 

 and the wootz (ufed into i' well cry flalli4;ed fplierule of fteel. 

 A thin cruft of revived lead was found below the v\'Ootz, vvhich 

 weighed 9 grains, or -i^-^i^ the weight oi wootz. 



2d Cake 



