6 LIVING LIGHTS. 



is continuously luminous, the phosphorescence disappearing 

 just after dissolution. Experiments have shown that in a 

 vacuum the light diminishes, carbonic gas producing the 

 same result. Humboldt refers to his luminous appearance 

 after bathing in water abounding in Noctilucce; and among 

 the curious experiments might be mentioned one where 

 print was read by a gobletful of these little creatures which 

 rendered them living lamps, literally. 



M. de Tessan, a French observer, has recorded a phenome- 

 enon, which, I should judge, was due to Noctilucce, with 

 perhaps the additional light of other forms. The accom- 

 panying picture on plate II. was made from his description, 

 showing the light, and people upon the shore endeavoring 

 to read by it. He writes: "On the 10th of April, in the 

 evening, the sea in the roadstead of Simonstown, Cape of 

 Good Hope, presented an extraordinary phosphorescence 

 of a most vivid character. At whatever points the phos- 

 phorescence was greatest, the water was colored on the 

 surface as red as blood ; and it contained such an immense 

 quantity of little globules that it had the consistency of 

 sirup. A bucket of water taken up at one of these points, 

 and filtered through a piece of linen, left in the filter a mass 

 of globules greater in volume than the water that had passed 

 through ;' in other words, the globules constituted more than 

 half of the whole quantity of sea water taken up in the 

 bucket. Viewed under the magnifying-glass, these globules 

 presented the appearance of little transparent and inflated 

 bladders, having on their surface a black point surrounded 

 with equally black radiating strice. . . . The least agitation 

 or slightest contact made them throw out a vivid greenish 

 light." 



