DEAD ANIMAL MATTER. 105 
Beccaria and Réaumur made many attempts to 
render the luminosity of the pholas permanent. 
The best result was obtained by placing the dead 
mollusk in honey, by which its property of emit- 
ting light lasted more than a year; whenever it 
was plunged into warm water the body of the 
pholas gave as much light as ever. 
Galeatus and Montius showed that vinegar and 
wine extinguished the hght of the dead pholades; 
that a heat of 45° Réaumur (56° centigrade) ex- 
tinguished this light, though it had increased in 
intensity up to that temperature, and that 1t could 
not afterwards be brought back again. 
Many other less remarkable experiments have 
been noted by the above-named authors. 
Most saltwater fish become phosphorescent in 
the dark, ike those mentioned above; and con- 
cerning those which inhabit fresh water I have 
heard it stated that the ovaries of the carp have 
been seen in a phosphorescent state. 
Mr. Canton has observed that several kinds of 
river fish could not be made to give light in the 
same circumstances in which sea-fish became lu- 
minous, but that a piece of carp made water very 
luminous, though the outside or scaly part of it 
did not shine at all. 
In 1672 Boyle published a paper in the ‘ Philo- 
sophical Transactions, contaming observations 
upon shining flesh. He treats in this paper of the 
