CONTENTS. vii 



PAOK 



America. 134. Eastern rivers. 135. Western rivers. 136. 

 The Mississippi and its tributaries. 137. Valley of the Missis- 

 sippi. 138. Red River, Arkansas, Ohio. 139. St. Louis. 

 140. Illinois . 145 



CHAP. III. 141. Source of Mississippi. 142. Missouri and its 

 tributaries. 143. The Amazons. 144. Its tributaries. 145. 

 The Orinoco. 146. The Rio de la Plata. 147. The river 

 system of Europe. 148. General plan of the rivers of the world. 

 CLIMATE. 149. Determines the animal and vegetable kingdoms. 

 150. Its dependence on latitude. 151. Explained by the varying 

 positions of the earth. 152. Spring equinox. 153. Sun vertical 

 at equator. 154. Oblique at all other points. 155. Its thermal 

 influence in different latitudes. 156. Position of the earth on 21st 

 June. 157. Days longer than nights in northern hemisphere. 



158. Temperature depends on sun's altitude and length of day.- 1 - 



159. Theimal influence greatest on 21st June in northern hemi- 

 sphere. 160. Position of the earth at autumnal equinox. 161. 

 Why the longest day is not the hottest. 162. Why the summer 

 is warmer than the spring. 163. The Dog-days. 164. Like 

 phenomena in the southern hemisphere. 165. Position of the 

 earth on 21st December. 166. Winter season explained. 167. 

 Why the shortest day is not the coldest. 168. The Tropics. 

 169. The sun can only be vertical within them. 170. Illustra- 

 tion of the varying position of the earth in the successive months. 

 171. The arctic polar circles and the frigid zones. 172. 

 Diurnal and nocturnal phenomena which characterise them. 173. 

 The torrid zone. 174. Sun vertical twice a year in the torrid 

 zone. 175. Temperate zone 161 



CHAP. IY. 176. Climate, dependent on elevation. 177. Vegetation 

 of the Himalayas. 178. Vegetation of the Andes. 179. Animals 

 of the tropics. 180. The Himalayas Animals inhabiting 

 them. 181. The local character of climate. 182. Heat 

 received from celestial spaces. 183. Why the temperature 

 of the earth is not indefinitely increased. 184. Effect of 

 clouds. 185. Effect of contact of air and earth. 186. 

 Thermal effects of a uniform surface. 187. Why this regu- 

 larity does not prevail. MOUNTAINS. 188. Maps and globes 

 in relief. 189. Johnston's Physical Maps. 190. Mountain 

 ranges not uniform. 191. Spurs. 192. Relief of the earth's 

 surface. 19:1 Effect of the contemplation of mountain scenery. 

 194. The Pyrenees. 195. The Alps. 196. Average height 

 of continents. 197. New mountain ranges possible. THE 

 OCEAN. 198. Greatest depth. 199. Uses of the ocean. 200. 

 General system of evaporation and condensation. 201. Climatic 

 effects. 2<>2. Ocean currents. 203. Antarctic drift current. 

 204. Its equatorial course. 205. Gulf stream. 20H. Course 

 and limits of ocean currents evident. 207. Ocean rich in animal 

 life. 208. Moral impressions 177 



