Rocks. 
61 
4. When separated from the rock the rounded grains 
differ in no way from grains of sand. 
5. Sandstones will often show other minerals besides 
sand grains. Silvery spangles of a mineral called 
mica can be detected. 
G. Sand is nothing more than broken particles of rock, 
mostly quartz, worn or abraded so as to become 
more or less rounded. 
7. When this sandstone is examined in a railway 
cutting or in a cliff, it is found to rest in layers, 
and the rock splits easily along these layers. 
8. If the sands of a river-bed or of the sea-shore were 
hardened into a solid mass, this would differ in no 
way from our sample of sandstone. 
0. Geologists can prove that sandstones were once 
sand, and that this sand was carried by running 
water to the sea, and settling down, layer above 
layer, on the sea bottom, became hardened into 
sandstone. 
10. The sandstone before us was broken by a geologist 
from a mass of work many hundred feet above the 
level of the sea. As this sediment, now hardened 
into sandstone, was once spread out over the 
bottom of the sea, it will be for us to inquire into 
those movements of the crust of the earth that 
have lifted a portion of the country from below 
sea level to a position many hundred feet above 
the sea. 
11. Without any further examination we are able to 
say that — Sandstone is a rock made up of 
rounded particles of other rocks or 
