108 THE HAWKESBURY SANDSTONE. 
_ way. In the first instance, it may be assumed that ne be 
iron was fairly uniformly diffused throughout the rock, 
nt preat deme 
aes 
tion in many parts, y idea as to the origin 
I regarded them as of fresh-water ori 
meappe and in the ok beds of the a gage 
arly all writers upon geology refer to instances 
of this particular kind in sedimentary rocks, and fig! 
structure are given by De la Beche, Lyell, and 
