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remains are to be found, in the interior part of the substance of the 
stones of which they are composed. 
Secondary mountains are, generally, marked by a softer outline ; 
and frequently possess the distinctive character, of being composed 
of, or at least of containing within them, the fossil remains of 
organized substances. They always rest on, and sometimes cover, 
primary mountains ; and very commonly, also, they lean on their 
sides, or invest them. The secondary mountains are formed, like 
the primitive ; either of one species of stone, or of strata of different 
species. Some are said to be derivative, being supposed to have 
originated from the disintegration of primitive mountains. 
The substances, of which the secondary mountains are chiefly 
composed, are lime-stone, swine-stone, marlite, chalk, and gypsum. 
They are also, sometimes, formed of indurated clay and lithomarga, 
jasper, porphyry, trap, silicious sand- stone, and other substances, 
which belong also to the primitive mountains. 
The various strata of which the earth is composed, as deep as the 
curiosity, and the necessities of man, have induced him to explore 
them, manifest, in a most striking manner, the wisdom displayed in 
the arrangement of the materials which compose the present world. 
The first layer, generally consisting of a rich black mould, is formed 
almost entirely of the remains of innumerable animals and vegetables, 
which, having lived through their destined periods, have been 
resolved into their first principles. This substance, laying at the 
surface, where alone it would be of utility, yields sustenance to the 
vegetable kingdom ; and thereby becomes the support of man, and 
of the rest of the animal creation. Beneath this is found, in many 
parts, as in the neighbourhood of this metropolis, a thick bed of 
clay, which furnishes the matter of which bricks and tiles, with the 
various species of pottery, and innumerable other articles, adapted 
to promote the comforts of social life, are formed. Next to this, in 
VOL. I. 
