Natural History, 8?c. 195 



everything distinctly, even to the masthead. The mate having alarmed 

 the master, put the helm down, took in sail, and called all hands up. 

 The light now spread over the whole sea between the two shores ; and 

 the waves, which before had been tranquil, now began to be agitated. 

 Captain Bonnycastle describes the scene as that of a blazing sheet 

 of awful and most brilliant light. A long and vivid line of light, 

 superior in brightness to the parts of the sea not immediately near 

 the vessel, shewed us the base of the high, frowning, and dark land 

 abreast of us; the sky became lowering and most intensely obscure. 

 The oldest sailors on board had never seen anything of the kind to 

 compare with it, except the captain, who said he had observed 

 something of the kind in the trades. Long tortuous lines of light, 

 in a contrary direction to the sea, shewed us immense numbers of 

 very large fish darting about as if in consternation at the scene. 

 The spritsail-yard and mizen-boom were lighted by the reflection 

 as though gas-lights had been burning immediately under them ; 

 and until just before daybreak, at four o'clock, the most minute 

 objects in a watch were distinctly visible. Day broke very slowly, 

 and the sun rose of a fiery and threatening aspect. Rain followed. 



Captain Bonnycastle caused a bucket of this fiery water to be 

 drawn up : it was one mass of light when stirred by the hand, and 

 not in sparkles as usual, but in actual coruscations. A portion of 

 this water, kept in an open jug, preserved its luminosity for seven 

 nights. 



On the third night the scintillations of the sea reappeared, and 

 were rendered beautifully visible by throwing a line overboard and 

 towing it along astern of the vessel. On this evening the sun went 

 down very singularly, exhibiting in its descent a double sun, and, 

 when only a few degrees above the horizon, its spherical figure 

 changed into that of a long cylinder, which reached the horizon. 

 In the night the sea became nearly as luminous as before. On the 

 fifth night the luminous appearance nearly ceased. 



Captain Bonnycastle is unwilling to attribute the above effect to 

 living animalcula ; but suggests the idea that it depends upon some 

 compound of phosphorus suddenly evolved and dispersed over the 

 surface of the sea. In such a compound he conceives the phos- 

 phorus or phosphoric acid to be afforded by exuviae or secretions of 

 fish, and the other constituents to be in some way connected with 

 those abundant oceanic salts, the muriate of soda and sulphate of 

 magnesia *. 



16. RENDING OP TIMBER BY LIGHTNING. 



Some pieces of an oak struck by lightning have been presented to 

 the Academy of Sciences by M. Arago, from the Duke de Chartres. 

 One was about three feet in length, and was split into lathes from 

 two to three lines in thickness and eight or ten lines in width ; the 



* Silliman's Journal, xviii. p. 187. 



02 



