WITH AGRICULTURE AND PLANTING. 483 



down and mingled together. To these operations are 

 to be attributed the various terminations of different 

 soils at horizontal distances, as well as the different al- 

 ternations of their strata at vertical ones. The power of 

 water in the formation of transported soil varies, not 

 only according to the different inclinations of its channel, 

 but also in regard to the form, size, and weight of the 

 parts carried oft* by it ; for which reason, in the forma- 

 tion of such soils, the same phenomena take place on a 

 large scale, that we see on a smaller, in performing the 

 operations of breaking and washing the ores of metals. 

 For the same reason that, in these processes, the larger 

 particles subside, while the smaller are propelled, from 

 which again the heavier particles of ore are sooner de- 

 posited than the lighter ; in plains in the vicinity of a 

 mountain, covered with transported soil, stones and de- 

 bris are usually seen first, then earth, clay, and sand mixed 

 together, and farther on, finer sand, with strata of clay. 



Transported or secondary soil, produced by water, 

 according to the mode of its formation, is divided into 

 four classes, viz. 1. Soil of Valleys; 2. River Soil; 

 3. Lake Soil ; 4. Marine Soil. 



.1. Soil of Valleys. It is washed down by rain and snow 

 water, and partly also produced by rivulets, which carry 

 off the loose parts from the declivities of mountains to 

 the plains. The nature of this soil in general clearly 

 shews the nearness of its origin. Its depth is always 

 greatest in the bottom of the valley, and gradually di- 

 minishes toward the declivities of the mountains. The 

 curvature of the different strata is usually accommodated 

 to the irregularity of its external form, so that when a 

 2 ah 9, 



