68 
WATERING. 
[chap. III. 
plant appears to have recovered its vigour. 
A great deal of the good produced by water¬ 
ing depends on the state of the ground; as 
when the ground is hard and compact, it is 
very possible to throw a great quantity of 
water upon it without doing any service to 
the plants. 
The hind of water used should also be con¬ 
sidered. The best is pond-water, as it is 
always mixed with air, and is, moreover, 
generally impregnated with decayed animal 
and vegetable matter; and the worst is clear 
spring-water, as it is always cold, and is sel¬ 
dom impregnated with air, or with anything 
but some mineral substance, which, so far 
from doing good, is positively injurious to 
the plants. Rain-water collected in open 
cisterns, and river-water, are both very suit¬ 
able; and when only spring-water can be 
obtained, it should be exposed for some time 
to the air before using it. It is always ad¬ 
visable to have the water at least as warm as 
the plants to be watered; and for this reason 
the water to be used in hot-houses and 
green-houses, is generally kept in an open 
vessel in the house some hours before using. 
