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SECOND BOOK. 
can pass freely through, it, and the roots can get to 
the food. 
5. If the soil is very ‘ loose ’ and sandy, water 
runs through too fast, and the plants may suffer 
from want of it. On the other hand, a stiff clay 
soil does not let the water drain off fast enough, 
and then the air is shut out. When that is the 
case we must not expect our plants to thrive. 
6. You understand easily how water can drain 
downwards, through the soil, but it is not so easy 
to see how it can rise. A simple illustration will 
help to make the explanation plain. Every boy 
knows how readily ink or water spreads through a 
piece of blotting-paper that is dipped into it, and 
how a whole lump of sugar or chalk will become 
wet if only the lower part rests in water. 
7 . The water rises and spreads through the small 
spaces or passages between the particles of the 
paper, sugar, or chalk. In the same way it rises 
through the spaces in the soil; but it does so best 
through clay, and least through sand. 
8. It rises to take the place of the water which 
has dried up at the surface of the soil, and in so 
doing it helps to bring the plant-food round about 
the roots of the plants. 
