142 
ANIMAL CURIOSITIES 
a little south of the Plata on one very dark 
night, the sea presented a wonderful and most 
beautiful spectacle. There was a fresh breeze, 
and every part of the surface, which during 
the day is seen as foam, now glowed with a 
pale light. 
“The vessel drove before her bows two billows 
of liquid phosphorus, and in her wake she 
was followed by a milky train. As far as the 
eye reached, the crest of every wave was bright, 
and the sky above the horizon, from the 
reflected glare of these livid flames, was not 
so utterly obscure as over the vault of the 
heavens.” 
It is also recorded that the captain of an 
American ship sailed through a zone of phos¬ 
phorescent sea in the Indian Ocean for a 
distance of nearly thirty miles ; while Humboldt 
records the fact that, having bathed in the 
sea where a number of Noctiluca were present, 
his body glowed with light for an hour after 
he had left the water. 
At one time it was thought that a phos¬ 
phorescent state of the sea was due to the 
water giving out light that it had absorbed 
and stored up during the daytime; while 
another theory was that the rotation of the 
earth set up friction between the air and the 
sea, thereby producing the light. 
