176 Dr. Hulme's Experiments and Observations 



the liquid seemed to have lost its luminous quality, except a 

 little glimmer floating at the top. It was then gently moved, 

 and the light diffused itself gradually through the whole liquid: 

 on agitation, the lucidness was much increased; and, the brisker 

 the motion, the more vivid was the illumination. 



SECTION VII. 



Spontaneous Light is not accompanied with any Degree of sensible 

 Heat} to be discovered by a Thermometer. 



EXPERIMENTS. 



Exper. 1, A luminous herring, and another that was quite 

 fresh and not luminous, were placed for a considerable time in the 

 same degree of temperature. A thermometer was then applied 

 to each of them, but no difference of heat could be discovered. 



Exper. 2. The soft roe of a herring, in an exceedingly lucid 

 state, and a thermometer, were kept together for some time in 

 the laboratory. The roe was then put upon the bulb of the 

 thermometer, without affecting it. 



Exper. 3. A mackerel, which shone with very brilliant light, 

 was also put to the test of a thermometer, but the instrument 

 remained stationary. 



Exper. 4. The bulb of a thermometer was surrounded by 

 many small pieces of shining wood, uncommonly luminous, 

 which were kept in that situation for some time ; but the light 

 made no alteration upon the thermometer. 



Exper. 5. Illuminated liquids, and spring water, being kept 

 together in the laboratory, always preserved the same degree of 

 temperature. 



