274 Causes of Phosphorescence. 



is certainly desirable that the geologist should feel and admit 

 that igneous fusion alone, as supposed to be recognized in 

 Plutonic rocks, or the ordinary action, whether mechanical 

 or chemical, of water, as recognized in Neptunian rocks, 

 cannot explain all the phenomena of rock formations and of 

 mineral veins ; whilst the term " Geyseriari' sufficiently ex- 

 plains the nature of the other actions, M. Dumont considers 

 to have shared in the production of the general effects ob- 

 served. — [Quarterly Journal of the Geological Society, vol. 

 ix., No. 35, p. 25.) 



Causes of Phosphorescence. 



It is well known that the waters of the sea, in some lati- 

 tudes and under certain circumstances, are phosphorescent, 

 producing a light more or less brilliant. This remarkable 

 phenomenon has alwa)S attracted the attention of travellers, 

 and various have been the explanations they have offered. 



Ehrenberg sums up, in the following manner, the import- 

 ant results of his labours : — 



1. The phosphorescence of the sea appears to be owing 

 solely to organized beings. 



2. A very great number of organic and inorganic bodies 

 shine in the water and out of the water in different ways. 



3. There is also a light from organized bodies, which is 

 probably owing to vital action. 



4. The active organic light shews itself frequently under 

 the form of a simple flash, repeated from time to time, spon- 

 taneous or provoked. Often also it appears under the form 

 of repeated sparks, following each other in quick successions, 

 under the influence of the will, and very similar to electric 

 sparks. Often, but not always, there is formed by this pro- 

 duction of sparks, a mucilaginous humour, gelatinous or 

 aqueous, which is diffused around in great abundance, and is 

 evidently placed in a secondary or passive state of phos- 

 phorescence, which continues a long time without requiring 

 any new influence from the organic being, and even lasts after 

 that has been divided or destroyed. 



