THE STUDENTS MANUAL
(1) Unstratified rock:
HI. PHYSICAL NATURE STUDY:
1. STUDY OF ROCKS: Geology 747; Evolution 636.
a. The main kinds of rocks in the earth's crust:
(a) Granite, rock made up of crystals
— mainly quartz: 1571; 792; 653; 1036.
1. The "hard-heads" of the fields: 553.
(b) Trap rock, dark, granular rock:
1938; 177.
1. The Palisades of the lower Hud-; son River: 1938; 894; 1571.
(a) Sandstone, rock made of grains of
sand held together by a cement: 1673; 1674.
1. Notice the material of which
gravel stones are made: sand 1673; gravel 796.
2. "Brown stone" houses: Ohio
1374; sandstone 1674.
(b) Limestone, composed mainly of
lime: 1072.
1. "Flag stone": 1773; chalk 363; limestone ledges 1072; marble 1167.
(c) Shale, a finely stratified rock
made from mud and silt: 1733; 406.
(d) Slate, a clay rock made from
shale by great heat: 1733. 1. Slate roofing: pencils 1444; slates 1733.
(e) Clay, mainly from the decay and
powdering of ©ther rock: 406. 1. Brick and potter's clay: 1538; 265.
(2) Stratified rock —which ^ is in layers:
b. The making of rock:
(1) igneous rock, rock which has been mol-ten, unstratified:
(2) Sedimentary rock stratified:
'(a) The first rock of the earth: 638;
1529; 747.
(b) Granite: 792; trap rock 1938;, hardened lava 1036.
(a) Made from material deposited by
water in the ocean, lakes and beds of streams: shale 1733; sandstone 1674; limestone 1072.
(b) How the material Is broken off
and worn away from the older igneous rock: sand 1673; Sahara 1654; earth 574; drift 553.
(c) How the material is carried by
water: alluvium 53; earth 574; chalk 363.
(d) How the material Is deposited:
sand 1673; earth 574; alluvium 53.
(e) Cementing of the particles to-
gether by lime anil silica: pebble 1437; shale 1733; silica 1757; lime 1071.
1. Effect of heat in this: mineralogy 1231; lime 1071.
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