Senate Doc. No. 84. 



Plate XLVIII. 



{A) GRANITE KNOB FROM WHICH THE FOREST, AND LATER THE SOIL, HAS BEEN LARGELY REMOVED. 



(See pp. 25, 26, 5G, 133, and PI. XIX.) 



{B) HUMUS AND UNDERGROWTH DESTROYED BY FIRE; SOIL BEING WASHED FROM ROCK BY RAIN. 



When the fires destroy the undergrowth and the humns the soil loses its spongy covering, and the water 

 from the heavy rains rushes down to the streams and causes floods, instead of being stored in the soil 

 for dry-season supply. (See pp. 25, 56, 133.) 



