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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



may determine the exit of the melted matter at the nearest points of 

 weakest resistance. 



91. Other consequences might arise from the different fusibility of 

 the various strata deposited in the bed of the ocean. Let us imagine 

 in the next woodcut (fig. 5), the two beds A and B to melt at a much 

 lower temperature than those between which they intervene. It 

 might happen, by the gradual rising of the isothermal surfaces, that 

 one or both of these strata should be melted ; and thus, supposing 



Fig. 5. 





all the beds originally to have contained marine remains, we might, 

 at a distant period, discover two interposed beds, without any trace 

 of such remains, but presenting all the appearances of former fusion, 

 resting on, separated by, and existing under, other beds of demon- 

 strably marine formation. 



If, during that former state of fusion, rents should have been 

 formed through several of the strata, injection of the liquid matter 

 might proceed from these melted beds, both upwards and down- 

 wards. If, on the contrary, older dykes had penetrated all the strata, 

 it is possible to suppose such a degree of fusibility in the older dyke, 

 or such chemical relation to the melted bed, that the portions of the 

 dyke passing through that bed should be obliterated, whilst those that 

 traverse the less fusible beds, protected from such action, should 

 remain unaltered, as in the annexed cut (fig. 6). 



Fig. 6. 



