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found in a great variety of places far away from the rock from which they were 
once a portion. 
I now come to the consideration of the last though not the least of the soil 
forming agents, viz., water. Iuse the term water here, in distinction to rain, 
although chemically the same, and apply it only where water occurs in some quan- 
tity, as in the case of streams, rivers, lakes, and seas. 
Water has two important methods of action, one a physical or mechanical, 
and the other a chemical one. I propose to consider each of these methods 
separately. 
By the first, or mechanical action, water abrades and wears away the surface 
of any rock with which it comes in contact, and then according to the state of 
motion or of quiescence of the water, the abraded particles are either carried 
out far from their parent rock or allowed quietly to sink to the bottom at the foot 
of the rock from which they were taken, 
A brief consideration of the abrading and transporting power of water will 
I think explain to us the three following phenomena so often seen in connection 
with soils. 
1st, why sometimes the soil is of the same nature and composition as the 
rocks in the immediate neighbourhood and sometimes of a totally different nature, 
2nd, why beds of one sort of material, such as gravel lie intermingled with 
beds of another sort of material such as clay, &c. 
3rd, why the same bed or stratum of soil is frequently found to be composed 
of a mixture of materials, such as sand and clay. 
With regard to the 1st of these cases, I think it is not difficult to understand, 
how slow, shallow streams, and the waves of lakes and seas, where no currents 
exist will not carry off their sediment to any great distance from the rock from 
which it was abraded, but will allow it to sink quietly to the bottom there to 
form a soil of the same nature as the rocks in the neighbourhood, and on the other 
hand, that rapid streams and currents, such as occur in mountainous districts do 
carry away their sediment to great distances, often hundreds of miles from the 
rocks from which it was abraded, and deposit it somewhere to form a soil often 
totally unlike in composition to the rocks in the vicinity, 
This transporting power of water which though familiar to everybody, and 
is seen in every ditch and puddle, is not perhaps seen in this couutry to the same 
extent as in some others where the mountains are higher, and therefore in order to 
give you a clear idea of what an important force it is in soil formation, I will 
adduce one case, namely that of the Ganges.’ 
Delta of Ganges. The river Ganges is one of the largest rivers of India, 
it forms the main drain of the North-Eastern portion of India, and pours its 
waters into the Bay of Bengal. Throughout its whole course it receives large 
contributions from tributary streams coming down from the lofty Himalayas, and 
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