on the terrestrial Rays that occasion Heat. 499 



thermometer, while the other received a thousand, directly from 

 the sun. Now, in order the better to compare the proportion of 

 light and heat scattered by different objects, we shall put these 

 413 rays equal to 1000 ; or, which is nearly the same, multiply 

 them by 2,421. Then, since the message card also scatters 

 1000 rays of light, as will be found in a table at the end of the 

 transmission table, our present object may be made a standard 

 for a comparison with the four following ones. 



196^ Experiment. 



Sun. Pink-coloured paper scattering. 



o' 64 64 



5 70 -66i . . . 6 : af = ,438 



Here a piece of pink-coloured paper, of the same dimensions 

 with the card of the last experiment, and placed in the same 

 situation, scattered, as we find by the same mode of multipli- 

 cation, 1060 rays of heat ; and, by our table, it scatters 513 of 

 light. 



197^ Experiment. 



Sun. Pale-green paper scattering. 



<* 64i 64X 



5 6 9 |. 66$ . . . 5| : *j. = ,370 



This piece of paper scatters 896 rays of heat, and 549 of 

 light. 



198^ Experiment. 



Sun. Dark-green paper scattering, 



5 %l <S7|.--4i:2i=:,5i3 



This paper scatters 1242 rays of heat, and only 308 of 

 light. 



