142 KING: KADAPAH AND KARNUL FORMATIONS. [PART III. 
Fig. 2la shows the frequent case of a band of slates being 
contorted in themselves, while the adjacent beds of quartzites are not at 
all so sharply folded. ` In such case, cleavage is only to be seen in the 
slates. Fig. 210 showing the rarer cases of quartzites contorted in 
themselves. In cases of quartzites being contorted in themselves! it 
always appeared as if the force exerted had been a quick, jarring one, 
so that the beds were crushed up in steps, and were not much moved out 
of the general plane in which they lay before the force was exerted: In 
such cases, the cleavage was more decided at these points of jerking. 
Such examples of cleavage of quartzites are very plain in the hilly 
ridges striking southwards from Giddaloor (east of the Nullamullays) 
to Kullsapaud. The northern ends of these ridges are well cleaved. 
Cleavage in the quartzites does not produce anything in the way 
E G2 aroma of a slate of quartzite for instance; but it gives 
Jleavag 
merely produces thin slabs. 
tolerably thin slabs of rock and flags. By 
the same force, there are also flags of slate.* 
The cleaved slabs of quartzites are from a quarter of an inch to two 
or three inches in thickness, and are often quite large enough for flooring 
or roofing houses. 
There is an intermediate form of rock between slates and quartzites, 
which is often met with over the Nullamullay country : and this may be 
called quartzose slates or slaty quartzite, according as the sandy or 
clayey element is most persistent ; but these terms are only used where 
cleavage is prevalent. The rock is generally of a grey or greenish 
color, and quartzose. There are plenty of quartzite flags of the same 
appearance in the Nullamullay country, but these split up in lamination, 
* Properly speaking, the term ‘flag’ ought only to be applied to thin beds of rock, 
or to slabs split off along planes of deposition, so that other flags might be distinguished 
by the term slaty flags or cleavage flags, where large slabs of rock are so produced. When, 
therefore, the terms *flaggy quartzites or limestones are used in this report, it must 
be understood that thin bedded varieties of the rocks are referred to. 
( 148 ) 
