63 



" I then drew up some more water, which shone as 

 before : part of this I kept during the night in an open 

 vessel, and part tightly corked up in a bottle ; and the 

 next night, on examining these two portions, I found 

 that the water in the open vessel shone pretty brightly, 

 but not so bright as it did ; and that which had been 

 corked up did not shine in the least the want of air 

 seeming to have killed the animals. They appear to 

 me to be coated with some phosphorescent matter ; 

 for I happened to rub one of them upon my fore-finger, 

 and it left a streak of light, for a few seconds, as long 

 as the first joint of my finger." The experiment with 

 the acid corroborates Dr. Ure's interesting one of a 

 similar description, and seems to add plausibility at 

 least to our view of this phosphorescence. Mr. Pfaff 

 has made some remarks on the phosphorescence of the 

 Baltic. This appears to be chiefly exhibited from the 

 end of summer to November, and is ascribed to the 

 presence of various molluscce. On an electric current 

 being passed through a tube containing sea water re- 

 cently taken up, there appeared a momentary exhibi- 

 tion of luminous points in continued motion : acids, 

 ammonia, and other excitants, produced a similar 

 effect. Mr. Bywater informed us that he had, some 

 years ago, increased the brilliancy of sea water in 

 one of the docks at Liverpool, by pouring on it acids, 

 &c., and he found, as Mr. Pfaff has since done, that 

 quiescence, such as that produced by oil, extinguished 

 the light. 



On our voyage from Leghorn to Civita Vecchia, we 

 remarked that the Mediterranean was particularly re- 

 fulgent, prior to a storm subsequently encountered. 

 The remarkably luminous phenomena of the sea at 

 Hastings, in December, 1822, was succeeded by a ter- 

 rific gale. We are in possession of numerous illustra- 



