152 Dr. Correa de Serra on a submarine Forest, 
sistence ; alterations which are produced by the development 
of their oily and bituminous parts, or by their natural progress 
towards rottenness. Such are the fossil vegetables found in 
Cornwall, by Borlase; in Essex, by Derham; in Yorkshire, 
by De la Pryme, and Richardson ; and in foreign countries, 
by other naturalists. These vegetables are found at different 
depths, some of them much below the present level of the sea, 
but in* clayey or sandy strata, (evidently belonging to modern 
formation,) and have, no doubt, been carried from their original 
place, and deposited there by the force of great rivers or cur- 
rents, as it has been observed with respect to the Mississipi.* 
In many instances, however, these trees and shrubs are found 
standing on their roots, generally in low or marshy places, 
above, or very little below, the actual level of the sea. 
To this last description of fossil vegetables, the decayed trees 
here described certainly belong. They have not been trans- 
ported by currents or rivers ; but, though standing in their 
native soil, we cannot suppose the level in which they are 
found, to be the same as that in which they grew. It would 
have been impossible for any of these trees and shrubs to 
vegetate so near the sea, and below the common level of its 
water : the waves would cover such tracts of land, and hinder 
any vegetation. We cannot conceive that the surface of the 
ocean has ever been lower than it now is ; on the contrary, we 
are led by numberless phenomena to believe, that the level of 
the waters in our globe is much below what it was in former 
periods ; we must therefore conclude, that the forest here de- 
* La Coudreniere stir les Depots du Mississipi. Journ. de Fbys. Vol. XXI, 
p. 230. 
