NATURAL HISTORY. 
cond—the more compact portions fuse before the 
blowpipe, sometimes into a more or less slaggy 
black glass, sometimes into a dirty white enamel, 
more or less mixed with black patches. 
THE GREEN SAND FORMATION. 
This is immediately incumbent on the red sand 
stone previously described ; in this district it occu- 
pies the upper parts of Milburn Down, of Great 
and Little Haldon, and two or three smaller conti- 
guous hills, which may be considered as interrupted 
portions of a range once continuous from thence 
across Black Down near Kentisbeare, to its dip 
beneath the chalk in Dorsetshire. Its direction is 
nearly the same as that of the primitive and transi- 
tion ranges—Its characters are chiefly that of a fine 
grained sand of various texture, from a friable 
character to a compact silt, and all more or less 
coloured by chlorite ; it frequently contains nodules 
of Gypsum, and abounds with fossil remains, chiefly 
univalve and bivalve shells. 
Incumbent on this formation both on the summit 
of Milburn Down, and the other hills, are strata of 
chalk flints—these beds were probably continuous 
also with those of Black Down, to their termination 
