on the Light emitted from various Bodies. 177 



SECTION VIII. 



The Effects of Cold on spontaneous Light. 



EXPERIMENTS. 



The Light of Fishes. 



Exper. 1 . Five small gallipots, containing three pieces of soft- 

 roe of herring, and two of the herring itself, all very luminous, 

 were placed in a frigorific mixture, composed of snow and sea- 

 salt; and, in about an hour and a half, the light was quite extinct, 

 and the bodies totally frozen. The gallipots were then removed 

 into a vessel of cold water, that their contents might be gradu- 

 ally thawed; which being done, they all recovered their pristine 

 luminous state. The pieces were afterwards observed to shine 

 during three succeeding nights. 



Exper. 2. A small phial, containing three or four drams of 

 liquid impregnated with light, was placed in a frigorific mixture. 

 As the liquid froze, its lucidness gradually diminished; and, when 

 it was quite congealed, the light perfectly disappeared. The 

 phial was then taken out, and put into cold water, at about 49* 

 temperature, that the ice might be gradually liquefied ; and, 

 when that was accomplished, the whole fluid became as lumi- 

 nous as before. 



The Light of shining Wood. 



Exper. 3. A fragment of shining wood was put into a small 

 wide-mouthed phial, which was plunged into a frigorific mix- 

 ture. As the cold affected the wood, the light gradually faded, 



mdccc A a 



