420 



KNOBLAUCH ON RADIANT HEAT. 



Table L. 



Table LI. 



Compare 

 p. 402 and 403. 



P.410and41l 



Sources of heat. 



Argand lamp 



Red-hot platinum 



Flame of alcohol 



Metallic cylinder at dark redness ... 



Gyp. 



sum. 



22-50 

 1650 

 12-37 

 27-25 



Deflection by 



Car- 

 mine. 



20-00 



* 



14-50 



* 



11-25 



* 



17-62 



Peroxide 



of 

 copper. 



22-50 

 16-50 

 14-37 

 27-50 



Red 



taffeta. 



23-75 

 14-37 

 13-75 

 21-50 



White 

 velvet. 



1650 

 10-75 

 10-00 

 15-75 



f Thus, among all the bodies subjected to examination, lamp-black and animal 

 charcoal (Table XLIX.) reflect every kind of radiant heat in the least degree; 

 and, excepting these, coke, grapliite and coal only exhibit a comparatively 



