INDEX 



Nebulae, 92 



Negroes, Nature's reason for the dark pigmentation of, 116 



Neolithic Age, The, 287 



Neptune, 119 



New Chum Mine, Temperature of, 83 



New Madrid, Earthquake at, 140 



Niagara Falls, The work of the, 52 



Nile, The Delta of the, 20 



Nineveh, 45 



North America, Ice in, 76 



North Garden Gully Mine, Temperature of, 83 



North Sea, The, how it was formed, 19 



North Sea, Ice in the, 75 



Ocean deposits, 61 ; life, 114 

 % Oceanic Era, The, 101 

 Old Red Sandstone, 212 

 Oolite, 66, 238 

 Ordovician Period, Life in the, 204 ; surface of the earth 



in the, 206 ; insect life in the, 206 ; fish in the, 207 ; 



the Trilobite, 207 

 Ordovician rocks, 202 

 Oreopithecus, The, 268 



Organisms, Multicellular and Unicellular, 111 

 Orion, 92 



Ostracoderm group, The, 215 

 Ostrich, The, 260 

 Oxygen, The action of, 47 



Palaeolithic Age, The, 287 

 Palazomastodon, The, 261 



302 



