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the ship goes swiftly in the night, in many seas the \\hok 

 breaking of the water will appear behind it as if on 

 fire, sparkling and shiniug all the way that it moves from 

 the ship, 



It is in this part as bright and glittering as if the 

 moon shone upon it, and chiefly when there is neither 

 moon nor stars, nor any light in the lanterns. But it is 

 not always the same : sometimes it is scarce perceiveable, 

 sometimes very vivid and bright. Sometimes it is only 

 just behind the ship, sometimes it spreads a great way 

 on each side. It commonly reaches thirty or forty feet 

 from the stern of the ship, but is fainter as it is farther 

 off. At the stern it is often so bright, that a person on 

 deck may see to read by it. The luminous water that 

 follows the ship is sometimes distinct from the rest of 

 the surface. Sometimes it is so blended with the ad- 

 jacent water, that the appearance is confused. The 

 luminous matter seems composed of small sparkles, 

 which are sometimes in the figure of a star, sometimes 

 it forms globules, without any radiations from them. 

 These are some of the size of a large pin's head ; some 

 larger, even to a foot in diameter. Sometimes the lu- 

 minous matter is in oblong squares, of three or four 

 inches. When the ship goes swiftly, these figures all 

 combine and form a sort of luminous whirlpool. Nor 

 does a ship only, but whatever moves swift through the 

 sea, cause the same appearance. Large fish, when they 

 swim near the surface, leave a luminous road between 

 them. So have a number of fish moving together.^ 

 And sometimes the throwing out a rope, or any thing 

 that breaks the surface of the water, will render it lu- 

 minous. If sea-water be taken up, and placed in a 

 vessel, as soon as it is stirred it will sparkle : and if a 

 linen rag be dipped in sea-water, and hung up, when 

 it is thoroughly dried, it will appear luminous on being 

 Tubbed in the dark; and when half dry, it need only 

 be shook, to shew a great number of sparkles. When 

 these sparkles are once formed, and fall on any solid 

 body, they will last a considerable time. If they remain 

 on the water they will soon go out. 



