A WORLD OF GARDENS 
97 
water, which weakens it. The only air they get 
is that which has been absorbed by the water. 
On the whole, water plants do not get along 
as well as land plants. The nearness of water 
is a great help, but there are disadvantages. 
Many a prospector, looking for gold in the 
desert country of Arizona or California, would 
have died of thirst if it had not been for the 
cactus plant. All he had to do was chop off 
the top of the cactus with his ax, and he would 
find sweet water stored in its barrel-like stem. 
Of course, he took a chance of getting his hands 
full of thorns, but when one is dying of thirst, 
thorns are not very important. 
It seems queer that the cactus, which grows 
in places where there is no rain for months and 
months—sometimes for years—should be able 
to have so much water to store away. The 
reason is that it is especially built to hold water 
and keep it from evaporating. When there is 
a rain, it stores up enough water to last until 
the next rain, even though that may be months 
away in the future. 
4 
Why is 
full of 
a cactus 
water? 
