98 On the Luminous Appearance of the Sea. 



the employment of philofophers ; and yet there are many 

 of them refpecting which our knowledge is verv uncertain. 

 But how is it poffible for fuch fhort-fighted beings as men 

 are, to have, at command, and employ in a proper manner, 

 all thofe external circumftances which are neceffary for the 

 thorough examination of fuch phenomena ? A thoufand 

 things occur daily in nature which it is impoffible for our 

 coarfe organs to perceive, and much more to obferve in a 

 perfecT: manner : in this paper, however, 1 fhall not defcend 

 to microfcopic objects, but offer a few remarks refpe&ing a 

 phenomenon winch frequently occurs, and which has at- 

 tracted the notice of many celebrated philofophers — I mean 

 the luminous appearance of the fea. This phenomenon, 

 which exhibits fo magnificent a fpcclacle to navigators, and 

 which, when beheld for the firft time, muft excite aftoniih- 

 ment, deferves certainly to be examined with more care and 

 attention. I fhall here, therefore, take a fhort view of the 

 information which has been collected on this curious fubjeci. 

 That the water of the fea fometimes exhibits a luminous 

 appearance in the night-time, efpecially when ftruck by the 

 rudder of a fliip, or ftrongly agitated by its refi fiance to the 

 motion of the veffel, is a cireumiiance well known ; and 

 this phenomenon appears fometimes, in calm weather, like 

 multitudes of fmall ftars difperfed over the furface of the fea. 

 It frequently happens, alfo, that the places only next the fliip 

 or the fliip's wake, or the track through which fifh have 

 paffed, appears luminous. The well-known Amcricus Vef- 

 pufius, the Italian navigator, according to Kirch cr, was the 

 firft perfon who obferved this cireumilance. 



In Lichtenberg's Magazine for the lateft Difcoveries in 

 Phyfics and Natural Htftory*, we find the following de- 

 fcription of this | henomenon as obferved in the Baltic : — . 

 "The phofphoiic phenomena in the Baltic generally appear 

 in thedarkeft nights, with an undulating motion, in the track 

 formed by yeflels in their progrefe through the waves. The 

 water fcems to emit a lively light, which is fometimes of a 

 pale red colour, and has the refemblance of fparks. Some- 

 jimes it exhibits the appearance of a regular ftream of fire in 



• * Vol. II. part iv. p. 48. 



the 



