into the gutter or an area, or finds its way down some grating.

Now just this, which we can watch whenever a heavy shower of rain
comes down on the road, happens also all over the world. Up in
the mountains, where there is always a great deal of rain,
little rills gather and fall over the mountain sides, meeting in
some stream below. Then, as this stream flows on, it is fed by
many runnels of water, which come from all parts of the country,
trickling along ruts, and flowing in small brooks and rivulets
down the gentle slope of the land till they reach the big stream,
which at last is important enough to be called a river.
Sometimes this river comes to a large hollow in the land and
there the water gathers and forms a lake; but still at the lower
end of this lake out it comes again, forming a new river, and
growing and growing by receiving fresh streams until at last it
reaches the sea.

The River Thames, which you all know, and whose course you will
find clearly described in Mr. Huxley's 'Physiography,' drains in
this way no less than one-seventh of the whole of England. All the
rain which falls in Berkshire, Oxfordshire, Middlesex,
Hertfordshire, Surrey, the north of Wiltshire and north-west of
Kent, the south of Buckinghamshire and of Gloucestershire, finds
its way into the Thames; making an area of 6160 square miles over
which every rivulet and brook trickle down to the one great river,
which bears them to the ocean. And so with every other area of
land in the world there is some one channel towards which the
ground on all sides slopes gently down, and into this channel all
the water will run, on its way to the sea.