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I.DSS   OK    IKON    I5\"    SS.Adl 1INC,    Ol'T   Cl I I'Ol.AS.            :» 2 1
•were losing" some metal by letting the bhist continually blow out of the shi;;1 hole, I decided to try, in the second heat quoted, to plui;' and tap the sla^-hole at intervals, or just a few minutes before tapping out. Ply doiii^-so we obtained, as shown, a, saving of six one-hum dredths of OIK* per cent, of the total weight of iron changed, or in oilier words, we saved 29 cents in the heat of 40 t» MIS at the risk of letting the iron or sla^ fill up the/ tuyeres, and hence Imnij; up the cupola. .By such a met hod of retarding melting to save a little iron, we ini^ht' lost many dollars in castings through bad melting or dull iron.
Where conditions are favorable to tapping a sla^~ hole, at intervals, or just before tapping out the; iron, on account of having a greater distance between the
tuveres and slai'"~hole, then  we.  had, the above iivnires . •»                                t                      ,*•>
clearly demonstrate* the economy of such practice; and it is one/ that, as a general thin;;'can be safely followed; but in cases where the. tapping; out and pb lining up of a slaiL>"--l)ole would require a man solely to look after it, nothing is !<» be saved bv this prael iee. \Ve used aJl pit;"; no scrap except iiii.; a few kk titles," which, fora 5o-ton h«-at would w«-ii.;h about two tons; and ('onnells-villecoke for fuel, of which .v»uo pounds were use<l for the bed ami .150 pounds between charges. The pi*.»- on bed was S,ooo pounds and between cliaj'^'es 6,000 pounds. We used limestone for a, ilux; for every three tons we used about 90 pounds, placed on top of ever}1 charge. There is no doubt that one or two hundredweight. <»f slai.^ could be added to the totals iMven above, whi«'h eouM be ;«;ather«Ml from the. skim-mini;-of ihf ladh- and tin- droppint-, of the bottoms. Our «Mj)pnrheii.sion as to loss of iron through slai;" was	r> ">'••	I I   O/..