NATURAL HISTORY. 
whilst the line of the Exe and the Sea Coast, on to 
Goodrington, form its other boundaries ; so that 
the spaces not occupied by the Lime or Slate, or the 
Amygdaloidal Trap, to be hereafter described, are 
filled by this formation: the strata vary much in 
thickness, and in general dip very gradually; they 
present themselves under various characters—viz ; 
that of a sand stone loosely compacted, or altogether 
pulverulent, (this is often intersected by thin plates 
of oxidulated Iron) —a marle more or less indurated— 
or a Breccia composed of fragments of various sizes, 
the base of which is usually marle of an unctuous 
and argillaceous character ; the marle having fre- 
quently those white and purple patches characteris- 
tic of that compound, 
This rock is often of sufficiently indurated cha- 
racter to be available as a building stone, and is 
then like Granite of a rhomboidal structure in the 
mass—argillaceous beds of Sand stone and of Brec- 
cia (conglomerate) often alternate with each other, 
and are inclined in various directions. The com- 
ponent parts, or rather the mineral contents of the 
more recent portion of this formation* are various 
—remains of Granitic, Porphyritic, and Greywacke 
rocks form a considerable part of the imbedded 
* It appears to be referable to two distinct members of 
the secondary class of rocks,—the old and the new red 
sand, (first and third sand stones of Humboldt) but this 
is a point not entirely settled, nor have their different 
limits in the County been accurately defined, 
