154 



THE GEOLOGIST. 



caused by evaporation or precipitation from an aqueous men- 

 struum. On the contrary there was no appearance of any 

 violent action or disturbance, such as would arise if an in- 

 jection had taken place. From these reasons it was inferred, 

 that the salt had been formed by precipitation. With respect 

 to the third subdivision, it was shown that salt is now 

 formed both by evaporation in salt marshes and shallow 

 lagoons, by the sea, and by volcanic action. 



After mentioning that, as yet, the cause of the saltness of 

 the sea was not accounted for. Dr. Marcet^s observations on 

 the analysis of the sea were mentioned. Amongst these the 

 most important were, that there was no satisfactory evidence 

 that the sea was more salt at great depths than at the surface ; 

 and that sea v/ater contained no muriate of lime. This sub- 

 stance is found, on the contrary, invariably in all the Cheshire 

 brines. A comparison was then drawn between the deposits 

 of Cheshire (where six beds of salt are seen in one section, 

 varying in thickness from 3 feet 4 inches to more than 115 

 feet, and occupying, with the accompanying strictly saliferous 

 beds, a depth of 350 feet) and the salt lakes of the present 

 day, where rarely more than one thin bed is found formed by 

 evaporation in summer, and disappearing in the winter, or 

 on irruptions of water. The change of seasons would cause 

 the latter, but successive subsidences must have taken place 

 to cause the deposit of beds such as seen at North wich. In 

 answer to any opinion that might arise that the sea might 

 have filled hollows made by subsidence, it was stated that no 

 remains had been found in the salt, unless the supposed 

 monads and vegetable fibre were such ; and that, if such an 

 irruption had taken place, such would, in all probability, have 

 been found. From the example of the salt at Weiliczka, it 

 was shown that wood and salt will be preserved in the salt. 

 The discharge of small fish at volcanic eruptions was men- 



