76o 



PHILOSOPHICAL TRANSACTIONS. 



[anno 1800. 



openly exposed to their action, the other thermometer, which received the same rays through the medium 

 of the interposed glass, rose only 1% degrees. Hence we calculate, that this glass stops 625 rays of 

 flame-heat, out of every thousand that fall on it. It stops only 86 rays of candle-light ; but this, having 

 been referred to before, will not in future be repeated. 



Expcr. 64. 



Exper. 65. 



Exper. 66. 



Exper. 67. 



Exper. 68. 



Exper. 69. 



Exper. 70. 



Exper. 71. 



Exper. 72. 



Exper. 73. 



Exper. 74. 



Exper. 75. 



Exper. 76. 



Exper. 77. 



Exper. 78. 



Exper. 79- 



Exper. 80. 



Exper. 81 \ 



