ANIMAL AND VEGETABLE PHOSPHOR1. 



with it; and in the night th<- same particles, as In- concluded, had 

 the appearance of lire. Taking n quantity of the water, the same 

 small sparks appeared whenever it was agitatnl ; but, as was ob- 

 served with respect to Dr. Beal's experiments, every successive 

 agitation produced a less effect than the preceding, except after 

 being suffered to rest awhile ; for then a fresh agitation would 

 make it almost as luminous as the first. This water, he observed, 

 would retain its property of shining by agitation a day or twoj 

 but it disappeared immediately on being set on the fire, though it 

 was not made to boil. 



M. Ant. Martin made many expeiiments on the light of fishes, 

 with a view to discover the cause of the light of the sea. He 

 thought that he had reason to conclude, from a great variety of 

 experiments, that all sea. fishes have this property ; but that it is 

 not to be found in any that are produced in fresh water. Nothing 

 in his opinion depended upon the colour of the fishes, except 

 that he thought that the white ones, and especially those that had 

 white scales, were a little more luminous than others. This light, 

 he found, was increased by a small quantity of salt; and also by 

 a small degree of warmth, though a greater degree extinguished 

 it. This agre<s with another observation of his, that it depends 

 entirely upon a kind of moisture which they had about thorn, and 

 which a small degree of heat would expel, when an oiliness remain. 

 ed which did not gire this light, but would burn in the fire. Light 

 from the flesh of birds or beasts is not so bright, he sajs, as that 

 which proceeds from fishes. Human bodies, he says, have some, 

 times eoiitted lit,ht about the time that they began to putrify, and 

 the walls and roof of a place in which tlead bodies had often 

 been exposed, had a kind of dew or clamminess upon it, which 

 was sometimes luminous ; and he imagined that the lights which 

 are said to be seen in bun ing-grounds may be owing to this 

 cause. 



From some experiments made by Mr. Canton, he concludes, 

 that the luminousness of sea.water is owing to the slimy and other 

 putresrent substances it contains. On the evening of the 14th of 

 June 1768, he put a small fresh whiting into a gallon of sea.water, 

 in a pan which was about fourteen inches in diameter, and took 

 notice that neither the whiting nor the water, when agitated, gave 

 any light. A Fahrenheit's thermometer, in the cellar where the 

 pan was placed, stood at 54. The 15th, at night, that part of 



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