A DROP OF WATER. 8 1 
been taken out of the air before it comes there. Again 
for example in England, the wind comes to Cumber- 
land and Westmoreland over the Atlantic, full of 
vapour, and as it strikes against the Pennine Hills it 
shakes off its watexy load ; so that the lake district is 
the most rainy in England, with the exception perhaps 
of Wales, where the high mountains have the same 
effect. 
In this way, from different causes, the water of 
which the sun has robbed our rivers and seas, comes 
back to us, after it has travelled to various parts of 
the world, floating on the bosom of the air. But it 
does not always fall straight back into the rivers and 
seas again, a large part of it falls on the land, and has 
to trickle down slopes and into the earth, in order to 
get back to its natural home, and it is often caught on 
its way before it can reach the great waters. 
Go to any piece of ground which is left wild and 
untouched, you will find it covered with grass, weeds, 
and other plants ; if you dig up a small plot you will 
find innumerable tiny roots creeping through the 
ground in every direction. Each of these roots has 
a sponge-like mouth by which the plant takes up 
water. Now, imagine rain-drops falling on this plot 
of ground and sinking into the earth. On every side 
they will find rootlets thirsting to drink them in, and 
they will be sucked up as if by tiny sponges, and 
drawn into the plants, and up the stems to the leaves. 
Here, as we shall see in Lecture VI L, they are worked 
up into food for the plant, and only if the leaf has 
more water than it needs, some drops may escape at 
G 
