INFUSORIAL ANIMALCULES. . 25 



on one very dark night, the sea presented a wonderful and most beautiful spec- 

 tacle. 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. Near the mouth of the 

 Plata some circular and oval patches, from two to four yards in diameter, shone 

 with a steady but pale light, while the surrounding water only gave out a few 

 sparks. The appearance resembled the reflection of the moon, or some luminous 

 body, for the edges were sinuous from the undulations of the surface. The ship, 

 which drew thirteen feet of water, passed over without disturbing these patches ; 

 we must therefore suppose that some of the luminous marine animals were con- 

 gregated together at a greater depth than the bottom of the vessel, or thirteen 

 feet beneath the surface of the sea." 



The same phenomenon is thus depicted in the glowing language of Colton : 

 " We had last night a splendid exhibition of aquatic fire-works. The night was 

 perfectly dark, and the sea smooth, and you might see a thousand living rockets 

 shooting in all directions from our ship, and running through countless configura- 

 tions, return to her, leaving their track still bright with unextinguishable flame. 

 Then they would start again, whirling through every possible gyration, till the 

 whole ocean around seemed medallioned with fire. We had run into an im- 

 mense shoal of porpoises and small fish ; the sea being filled at the same time 

 with animalcule, which emit a bright phosphoric light when the water is agi- 

 tated. The chase of the porpoises after these small fish created the beautiful 

 phenomenon described. The light was so strong that you could see the fish 

 with the utmost distinctness. They lit their own path like a sky-rocket in a dark 

 night ; and our ship left the track of its keel in the wave for half a mile. I have 

 witnessed the illumination of St. Peter's, and .the castle of Michael Angelo, at 

 Rome, and heard the shout of the vast multitudes as the splendors broke over 

 the dark cope of night, but no pyrotechnic displays ever got up by human skill, 

 could rival the exhibitions of nature around our ship." That the cause of this 

 brilliant phenomenon is correctly assigned to marine animals has been proved 

 by the examination of the luminous water, for if it is placed in a tumbler and 

 agitated, they immediately emit light in momentary sparks. Some of these crea- 

 tures are of considerable dimensions and others barely visible, but a great pro- 

 portion are entirely microscopic, and require the aid of powerful instruments in 

 order to perceive them and investigate their forms and nature. 



The various species of Infusoria which illumine the ocean, are extremely small 

 in size ; the largest do not exceed one-hundredth of an inch in extent, while the 

 least, hardly attain the length of one-twelve hundredths of an inch. The phos- 

 phoric light emitted by these creatures, is regarded by naturalists as the effect 

 of a vital action ; it appears as a single spark like that of the firefly, and can be 

 repeated in a similar manner at short intervals. 



