ILLUSTRATIONS IN THE TEXT 



FIG. PAQB 



168. Map and sections of a stream meander 163 



169. Tree undermined on the outer bank of a meander .... 164 



170. Diagrams to show the successive positions of stream meanders . . 164 



171. An ox-bow lake in the flood plain of a river 165 



172. Schematic representation of a series of river terraces .... 165 



173. " Bird-foot " delta of the Mississippi River 167 



174. Diagrams to show the nature of delta deposits as exhibited in sec- 



tions ... 168 



175. Gorge of the River Rhine near St. Goars 169 



176. Valley with rounded shoulders characteristic of the stage of adoles- 



cence . 170 



177. View of a maturely dissected upland 170 



178. Hogarth's line of beauty . . 171 



179. View of the oldland of New England, with Mount Monadnock rising 



in the distance 171 



180. Comparison of the cross sections of river valleys of different stages . 172 



181. The Beavertail Bend of the Yakima River 173 



182. A rejuvenated river valley ......... 174 



183. Plan of a river narrows ......... 174 



184. Successive diagrams to illustrate the origin of " trellis drainage " . 175 



185. Sketch maps to show the earlier and present drainage near Harper's 



Ferry 176 



186. Section to illustrate the history of Snickers Gap 177 



187. Character profiles of landscapes shaped by stream erosion in humid 



climates . 177 



188. Diagram to show the seasonal range in the position of the water table 180 



189. Diagram to show the effect of an impervious layer upon the descend- 



ing water 181 



190. Sketch map to illustrate corrosion of limestone along two series of 



vertical joints .......... 181 



191. Diagram to show the relation of limestone caverns to the river system 



of the district 182 



192. Plan of a portion of Mammoth Cave, Kentucky 183 



193. Trees and shrubs growing upon the bottoms of limestone sinks . . 183 



194. Diagrams to show the manner of formation of stalactites and stalag- 



mites ....... 185 



195. Sinter formations in the Luray caverns ...... 186 



196. Map of the dolines of the Karst region 187 



197. Cross section of a doline formed by inbreak ..... 187 



198. Sharp Karren of the Ifenplatte 188 



199. The Zirknitz seasonal lake 189 



200. Fissure springs arranged at intersections of rock fractures . . .190 



201. Schematic diagrams to illustrate the different types of artesian wells . 191 



202. Cross section of Geysir, Iceland . . 192 



203. Apparatus for simulating geyser action 193 



204. Cone of siliceous sinter about the Lone Star Geyser . . . .194 



