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El'TKCT   OF   FUKL,   KLUXKS,   TKM I'KR AT rj R K,   KTC.     305
In coonectioffi with a study of this chapter, readers are referred to tests showing losses of silicon and manganese, and <4'ains in sulphur, phosphorus, and carbon found in Tables 73 and 76, pa^es 334 and 3,1 i. It is to he understood that the fore<n>in^" pat^es of this chapter deal with cupola practice only; and as the author has had no opportunity of late for experimenting with results to he derived from re-melting iron in. an tl air furnace.1/ he cites the following extract from Sir William Fair-bairn's report before the British Association of Science on the effect of re-melting iron in an li air furnace " eighteen times, in which he describes the action of re-melting" as follows:
Phosphorus increased from 0.47 to o.C>i. This was probably clue to loss of metal by oxidation. Manganese decreased from [.75 to .12. Tliis would tend to improve the mclal (luring (lie earlier meltings. Silicon was reduced from .\.'2'2 to i.SS. The first effect of this reduction was to produce softer metal and lower combined earlx >n, since silicon \vas present in quant it y in excess of that necessary for (he softest metal. ( )n further I'eduel ion of silicon Hie meln.l became stronger and harder. I*ut in thi'Sccv-pcrimcnts the reduction was not carried sufficiently far to cause any deterioration due to sufficiency of silicon. Sulphur increased from .os to .:ťo, and Ibis is OIK- of ihc most important changes which took place, (he increase in sulphur tending; in the same direction as I he. loss of silicon, vi/,., the production of hi^h combined carbon. The combined carbon increased considerably after the eighth melting, ultimately reachhu1; to over two per cent. By Fairbairn's experiments \vc find that the results of re-melting in an air furnace are in part similar t<> those of a cupola, and in both cases it is a subject as necessary t<> he understood, in order to obtain desired ends, as is that of knowing the chemical properties of the iron before it is ehanjvd.
There have been experiments conducted in order t<>t was fully demonstrateduois Iron Co., Illinois Steel Co., Jefferson Iron Co., Kittan-ning Iron & Steel Co., C. A. Kelly Plow Co., Lebanon Furnace, Longdale Iron Co., Lackawanna Iron & Steel Co., Logan Iron........................   16,720     "                                     t-