KXOBLAUCH ON RADIANT HEAT. 



399 



deflections was, in various surfaces of woods and metals, for all 

 the diathermanous media used, and at greater deflections than 

 those above mentioned : — 



Table XXIX. 



tion after the insertion when the heat of the Argand lamp is reflected by 



radiated through the diathermanous media in exactly the same 

 proportion. Thus, on inserting the red glass, each deflected the 

 needle of the galvanometer 8°-14 to 8°-l7, the direct deflection 

 being 13°, and on inserting the calcareous spar, 17°*62, when 

 the direct deflection amounted to 25°. They are however well 

 distinguished by the heat diffusely reflected by a metallic sur- 

 face, which, like that unreflected, on inserting the glass, caused 

 the needle to recede from 13° to 7°'67, and on introducing the 

 calcareous spar, from 25° to 14°*44. 



The subjoined table contains the details of the observations on 

 these and some other reflecting surfaces, as found with the dif- 

 fei'ent diathermanous bodies : — 



Table XXX. 



