264 PHYSIOGNOMY OP PLANTS. 



through the stratum of water; while electric fishes, in connection 

 with the galvanic circuit, decompose water and impart magnetism to 

 steel bars, as I showed more than half a century ago (Versuche 

 iiber die gereizte Muskel- und Nervenfaser, bd. i. s. 438-441, and 

 see also Obs. de Zoologie et d' Anatomic comparee, vol. i. p. 84) ; and 

 as John Davy has since confirmed (Phil. Trans, for 1834, Part ii. 

 pp. 545-547), do not pass a flash through the smallest intervening 

 stratum. 



The considerations which have been developed make it probable 

 that it is one and the same process which operates in the smallest 

 living organic creatures, so minute that they are not perceived by 

 the naked eye in the combats of the serpent-like gymnoti in 

 flashing, luminous Infusoria which raise the phosphorescence of the 

 sea to such a degree of brilliancy ; as well as in the thunder-cloud, 

 and in the auroral, terrestrial, or polar light (silent magnetic light- 

 nings), which, as the result of an increased tension in the interior 

 of the globe, are announced for hours beforehand by the suddenly 

 altered movements of the magnetic needle. (See my letter to the 

 Editor of the Annalen der Physik und Chemie, bd. xxxvii. 1836, 

 s. 242-244.) 



Sometimes one cannot, even with high magnifying powers, dis- 

 cern any animalcules in the luminous water ; and yet, whenever 

 the wave strikes and breaks in foam against a hard body, a light is 

 seen to flash. In such case, the cause of the phenomenon probably 

 consists in the decaying animal fibres, which are disseminated in 

 immense abundance throughout the body of water. If this lumi- 

 nous water is filtered through fine and closely woven cloths, these 

 little fibres and membranes are separated in the shape of shining 

 points. When we bathed at Cumana in the waters of the G-ulf of 

 Cariaco, and afterwards lingered awhile on the solitary beach in the 

 mild evening air without our clothes, parts of our bodies continued 

 luminous from the shining organic particles which had adhered to 

 the skin, and the light only became extinct at the end of some mi- 

 nutes. Considering the enormous quantity of animal life in all tro- 

 pical seas, it is, perhaps, not surprising that the sea water should be 

 luminous, even where no visible organic particles can be detached 

 from it. From the almost infinite subdivision of the masses of 



