What is the summary of the poem "Rain in Summer" by Longfellow?

This famous and beautiful poem begins by stating how
beautiful rain is after a long, hot and dusty summer. The sound it makes and the impact
it has is explored and evoked in the poem, for example in the following
passage:

How
it clatters along the roofs,

Like the tramp of
hoofs

How it gushes and struggles
out

From the throat of the overflowing
spout!

Note the way that the
sound of the rain is created through the onomatopoeia of "clatter" and how the simile
compares the sound to the "tramp of hoofs."

Then the poem
goes on to describe the different reactions of many different types of people to this
rain and how it helps and heals them. The sick man's fever is cooled, the boys find a
natural source to express their joy and merriment in the rain, to the countryside the
rain is incredibly welcome, the "patient oxen" offer more thanks than man is able to for
the rain and lastly the farmer is also incredibly grateful for the "gain" that will come
to him through the rain.

The poet, however is able to see
all of these things and so much more, including "Things manifold / That have not yet
been wholly told." Just like the rain, the poet is able to take a universal view and
access places through his imagination that only water can seep into. Lastly, the seer is
shown to reflect on the endless cycle of life and death and to be able to
see:

The
Universe, as an immeasurable wheel

Turning
forevermore

In the rapid and rushing river of
Time.

The poem thus begins by
focusing on the particular, the rain falling in summer, and this thus develops into a
meditation on the mystical workings of the entire universe.