IOi{ On the "Luminous Appearance of the Sea. 



ance of fea water is owing to a commencement of putrefac- 

 tion *. ' 



Another circumftance which has been proved by thefe 

 nations is, that heat deprives putrid bodies of their lu- 

 minous property. This circiunftance did not efcape Canton; 

 for he remarked that, though a ftrong fummer' heat pro- 

 moted putrefaction, a Heat twenty degrees higher than that 

 of the blood feemed to prevent it. This he difcovered hy 

 the following experiment : — He put a fmall piece of a fifli 

 which had become luminous, into a globe of thin glafs, 

 immerfed it in water heated to 118 s of Fahrenheit, and ob- 

 ferved that it was deprived of its luminous property in lefs 

 than a minute: on being taken from the water, however, it 

 recovered its luminous property in ten feconds, but the light 

 it emitted was not fo ftrong as before. 



Spallanzani does not agree in opinion with Canton, that 

 the luminous appearance of fith arifes from putrefadlion f. 

 He repeated Canton's experiments wilh a variety of fifb, 

 but he fucceeded only with a very few of them. Thofe 

 which did not emit light he found in general to be the fat- 

 ted:, though, according to Canton, thefe ought, above all 

 others, to communicate a luminous appearance to fea water. 

 Another circumftance, which ft-ems contrary to Canton's 

 hypothecs, is, that if the nocturnal luminous appearance of 

 the fea were occasioned by the oleaginous remains of putrid 

 £fh> as thefe remains always float at the furface the light 

 ought to be confined to the iurfaee of the water; which ex- 

 perience (hows not to be the cafe. 



Vianelli, a phyfician of Chioggia in the neighbourhood 

 of Venice];, Grizzelini, a Venetian phyfician, the abbe 

 Nollet§, and Dr. Prieilley, afcribe the luminous appearance 



* That fevtral kinds of fun, fuch, for example, as the fefia t ihine in 



T Memorie di Matematica e Fifica della Soc. Italiana, Vol. II. p. 6oj. 

 + Nuove Sroperte intorrio le Luci notturne dell' Aqua Marina. — 



§. NdSavcIlcs Obfervat. fur la Scolnpendre ^larine, and the abbe Nollet, 

 hi the M email es de L'Acad. des Sciences 17^0, p. 8&. 



of 



