LUTHER BURBANK 
certain amount of water. But cells that thus take 
in water at once give up a portion of it to their 
neighbor cells, and these in succession pass it on 
to their neighbors. Thus, through an endless 
series of reactions between the cells the water is 
carried up in the living wood next to the bark of 
the tree and ultimately to the leaves. 
NATuURE’S BUCKET BRIGADE 
The process is not altogether unlike the activi- 
ties of a fire brigade in the rural districts, where 
a line of men is formed from the fire to the near- 
est well, and buckets are passed from hand to 
hand. 
If the fire is in the upper story of a building, 
men on the ladder may similarly hoist one bucket 
after another from hand to hand. And in this 
case it is obvious that there is no question of a 
column of water to exert pressure. The water is 
transported in individual buckets each one inde- 
pendent of the others. 
And it would appear that the case of the water 
in the plant cells is closely comparable. Each 
pair of cells constitutes a system more or less in- 
dependent of all the others. 
The forces of osmosis, operating between each 
pair of cells, are in command of the situation and 
so break the continuity that all semblance to a 
continuous column of water is lost. 
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