on the terrestrial Rays that occasion Heat. 481 



This experiment being made early in the morning, before 

 the temperature of the room was come to its usual height, the 

 assistant thermometers shewed a gradual rising of lj- degree in 

 the 5 minutes : they are in general very steady. The glass 

 stops 685 rays of fire-heat. 



12 7 th Experiment. 



Fire. Pale-green glass. 



o' 65% 65 



5 85 71^ . .. 19^: 6 = ,312 



It stops 688 rays of fire-heat. 



128^ Experiment. 



o' 



Fire. , 



Dark-green glass. 



68 



68 



88^ 



73i • • • 20 i : 5i cor. — £° = ,255 



5 



It stops 745 rays of fire-heat. 



129^ Experiment. 



Fire. Bluish-green glass. 



o' 68i 68i 



5 87 74i--- l8 i : 5f = >3°4 



It stops 696 rays of fire-heat. 



lgoth Experiment. 



Fire. Pale-blue glass. 



o' 68^ 68 



5 86^ 7St--.i7f ^=?,3 2 4 



It stops 676 rays of fire-heat. 



