Origin of the Mountains. 
295 
and Shales. All are now ready; it only needs the 
mighty power that the earth holds pent up within 
her, to come into play, and lift the accumulated 
sediments above the sea. 
We have proceeded far enough by this to dis- 
tinguish three stages in the building of the Blue 
Mountains — 
1. Deposition of the sediments. 
2. Lifting up of the sediments. 
3. The carving and sculpturing of the uplifted 
rocks. 
In a sense the period of the deposition of the 
sediments during the Permo-Carboniferous and Tri- 
assic, was the age in which the building of the 
mountains was really done. But it is equally correct 
to say that, were it not for subsequent upheaval, the 
Mountains would not exist as such. As to the fact 
of the sedimentary strata being lifted up, there is no 
room for doubt — marine beds occurring nearly 3,000 
feet above sea-level — the only room for discussion 
being as to the nature of the upheaval. 
The Blue Mountains as such had no existence in 
Triassic times. At the close of that period a basin 
extended from Mount Lambic to a point at present far 
out to sea. The western half of this basin is new 
elevated, while the eastern half is approximately in its 
original position. There is reason to believe, however, 
that the eastern half was also elevated, but is now 
again at sea-level, through a subsequent depression. 
There are objections to be answered, and difficulties to 
