147 
A STEEP CLIMB 
T is all very well, you may think, to say that the 
pressure from the root sends the water up through 
the stem; but when we cut across such a stem as a tree 
trunk, one finds it full of wood, with a little tightly 
packed soft stuff in the center, and not hollow like a 
water pipe, as one would suppose from all that has been 
said about the way the water rises in the stem. 
No, a stem is not a hollow pipe, or even a bunch of 
hollow pipes, it is true; and it does seem something of 
‘a question, how the water can force its way through all 
this wood; and even if one hears how it is done, it is 
not an easy thing to make clear either to grown people 
or to children. But I will see what I can do; and I know 
that you really love these plants and trees, and will try 
to be a little patient with them and with me. 
The water, or liquid, when it mounts a stem or tree 
trunk, takes a path that leads through the new-made 
cells. Each young cell wall is made of such delicate 
material that it allows the water, or broth, to filter 
through it, just as it would pass through a piece of thin 
cloth. And so it makes its way from cell to cell, along 
the stem, more slowly than if it were passing through a 
hollow tube, but almost as surely. It is true, the earth 
broth does not reach the leaves above without having 
given up something to the little cells along the road. 
These seem to lay hold of what they specially need 
for their support, while the rest is allowed to pass on. 
I want your teacher to prove to you by a little experi- 
ment that water makes its way up a stem. 
