knoblauch on radiant heat. 

 Table XLIX. 



direct radiation when the heat is reflected by 



421 



Table L. 



direct radiation when the heat is reflected by 



Table LI. 



direct radiation when the heat is reflected by 



feeble diffugion, which is also apparently independent of the nature of the source 

 of heat; consequently these only can be considered " black bodies" as regards 

 luminifcrouB and calorific rays. 



