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ALE DILIGENT - REE 
OW we have learned three things about plants, 
and especially about leaves. We have learned — 
1; That they perspire. 
. That they eat and drink. 
3. That they ‘breathe. ; 
_They perspire when the water passes through the 
No 
leaf mouths into the air. 
They eat when Leaf Green and Sunbeam together 
manage to take the carbon out of the carbonic-acid gas 
which has made its entrance through the leaf mouth 
and the cell wall. They drink when the roots suck in 
water and earth broth. 
They breathe when the leaf mouths take from the air 
the oxygen, and give back to it carbonic-acid gas. 
The veins and veinlets, of which you see so many 
running through a leaf, act in something the same way 
as the water pipes of a city; for through these veins 
the watery food, the earth broth, is carried to the dif- 
ferent. cells. 
When one knows all that we know even now about 
a plant, one looks at a tree covered with leaves with a 
good deal of admiration. 
Just think of what is being done inside that quiet- 
looking tree! Think of the millions of cells that go 
to make it up, each cell having its own work to 
do! Think of the immense amount of business being 
carried on within the trunk, inside the branches; jand 
especially in each green leaf! And when you have the 
