IN NEWCASTLE COAL PITS. 457 
Lindley and Hutton state (Fossil Flora, Vol. 
I. page 16) that '* It is the beds of shale, or 
argillaceous schistus, which afford the most abun- 
dant supply of these curious relics of a former 
World ; the fine particles of which they are com- 
posed having sealed up and retained in wonderful 
perfection, and beauty, the most delicate forms 
of the vegetable organic structure. Where shale 
forms the roof of the workable seams of coal, as 
it generally does, we have the most abundant 
display of fossils, and this, not perhaps arising 
so much from any peculiarity in these beds, as 
from their being more extensively known and 
examined than any others. The principal de- 
posit is not in immediate contact with the coal, 
but about from twelve to twenty inches above it ; 
and such is the immense profusion in this situa- 
tion, that they are not unfrequently the cause of 
very serious accidents, by breaking the adhesion 
of the shale bed, and causing it to separate and 
fall, when by the operation of the miner the coal 
which supported it is removed. After an exten- 
sive fall of this kind has taken place, it is a cu- 
rious sight to see the roof of the mine covered 
with these vegetable forms, some of them of great 
beauty and delicacy ; and the observer cannot 
fail to be struck with the extraordinary confusion, 
and the numerous marks of strong mechanical 
action exhibited by their broken and disjointed 
remains." 
