474 ® r - Herschel's Experiments on the solar, and 



io6tb Experiment. 



Red rays. Pale-blue glass. 



It stops 700 rays of the same sort of heat. 

 107^ Experiment. 



Red rays. Dark-blue glass. 



o' 67 6jjr 



5 68| 68|-...if :if = ,929 



This glass stops only 71 rays of the same sort of heat. 



loStb Experiment. 



Red rays. Indigo glass. 



o' 68i 68^ 



5 7oi 69^- . . . 2 : i£ = £33 



It stops 367 rays of the same sort of heat. 



logtb Experiment. 



Red rays. Pale-indigo glass. 



o' 69 68 



5 7 1 70 ... 2 : if = ,687 



It stops 313 rays of the same sort of heat. 



notb Experiment. 



Red rays. Purple glass. 



5 5H 57i • • ■ »i : i£ = »55^ 



It stops 444 rays of the same sort of heat. 



