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Drs. J. T. Bottomley and J. C. Beattie. 



Fia. 3. — Curves showing emission of heat from Pt^ (bright) and Ptg (sooted), ironr. 

 the same hank of wire, diameter 0*0542 cm., at various temperatures. 



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TemperaCure in decrees CenCi^rade. 



