51 o Dr. Herschel's Experiments on the solar, and 



greenish crown glass stops only about one-fourth more of the 

 former than of the latter ; but, as coloured glasses take in a 

 much greater range, I will now also give a tabular result of the 

 experiments that have been given relating to them. 



Dark-red 



Orange 



Yellow 



Pale-green 



Dark-green 



Bluish-green 



Pale-blue - 



Dark-blue 



Indigo 



Pale-indigo 



Purple - 



Violet 



From this table, I shall also point out a few of the most 

 remarkable results. A yellow glass, for instance, stops only 

 333 rays of heat, but stops 819 of light : on the contrary, a 

 pale blue stops 812 rays of heat, and but 684, of light Again, 

 a dark blue glass stops only 362 rays of heat, but intercepts 

 801 of light; and a dark red glass stops no more than 606 

 rays of heat, and yet intercepts nearly all the light ; scarcely one 

 ray out of 5000 being able to make its way through it. 



Before I proceed to a more critical examination of these 

 results, it will be necessary to add also a table of the same kind, 

 collected from the experiments with liquids. 



Table II. 







ops 800 rays ( 



Df heat, and 999-^ 



606 - 



- 



999^o 



- 604 



- 



779 



- 333 - 



- 



819 



6 33 



- 



535 



- 849 - 



_ _ 



949 



768 



- 



7 6 9 



- 812 - 



- 



684 



362 



-■ 



801 



- 633 - 



- 



999to 



532 



_ . 



978 



583 " 



- 



993 



489 - 



- 



955 



