HOW A PLANT FEEDS. 
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their substance is water, and even the driest kinds 
of timber have much water in them. 
5. This water is held in the cells, whose walls are 
so thin that it passes through them from one cell to 
1, Seedling with soil attached to Root-hairs; 2, the same washed clean; 3, A Root-tip 
with Root-hairs (magnified); 4, Root-hairs (much magnified) with soil on them. 
another. And that is the way the food is carried 
along. 
But how does the food get into the plant? Most 
of it is taken in by the leaves, and some, besides 
water, goes in by the roots. 
6. On the delicate little feeding-threads of any 
root, numbers of the cells lengthen out so that they 
appear like little hairs, and are called root-hairs. 
It is these that gather from the soil the necessary 
