XIV CONTENTS. 



PAGE 



APPENDIX. 

 FORMATION AND GROWTH OF SOIL OR SURFACE-MATTER . . 223 



Rock weathering and disintegration, 223 ; Some rocks \ 

 weather more than others, 224 ; Mud-land of Wexford, 225 ; 

 Chemical actions, 226 ; Darwin's theory of worm-work, 227 ; 

 Irish moors, 229 ; Vegetable growth combined with worm- 

 work, 230 ; Subsoils, 232 ; Growth of soil at Caerleon, 234 ; 

 Soil due to water and wind, 236 ; Kutch, 237 ; Ants, 237 ; 

 Other soil-producing animals, 239 ; Guano, 240. 



