22 TALKS ABOUT THE SOIL. 



cliff is very rapid, this other and probably much older 

 work was very slow. 



This weathering of the rocks has been going on ever 

 since the world began. Heat, cold, water, air, ice, 

 the wind, expansion and contraction, storms, all the 

 phenomena we have been studying in our observations 

 of the weather, unite to break down and destroy the 

 rocks. The work is still going on every day. It can 

 be seen easily all along the Palisades on the Hudson, 

 and on every rocky hill and mountain. Look about 

 among the hills in your neighborhood, and make care- 

 ful explorations and observations of the effects of the 

 weathering upon the rocks. Put down full notes of 

 the work, whether it seems to be going on slowly or 

 rapidly ; and note particularly what seems to be the 

 chief influence, the rain, or the frost. In some 

 places you will find the rocks breaking down into sand, 

 dust, and powder, during every rain. In others you 

 will find it hard to tell whether the work is going on or 

 not. In all it is going on, and good observation will 

 soon enable you to find out its cause. 



From the railroad that creeps along under the 

 shadow of Schunemunk, looking south, can be seen 

 the profile of the mountain. The slope is peculiar. 

 At the top it is abrupt and steep ; then it softens, and 

 with a lovely curve the graceful outline melts gently 

 away into the level meadows of the beautiful valley. 

 The mountain is wasting away; and its ruins are 

 slipping, slipping ever, down into the fertile valley. 

 The soil-makers are at work here, as everywhere, 



