In “the negro speaks of rivers,” how does hughes use images of rivers, dark and light, to communicate the experience of his race?

Hughes target reader is for non-black people. He is trying to bring out a feeling of wonder and respect. The words he has chosen for the poem evoke a sense of depths of time. In the poem, he talks about the rivers that are older than human blood. Likewise, he talks about dawns being young. With these, it makes the readers feel a sense of awe at how much time he is talking about. By connecting this depth of time to the experience of the black people, he is trying to make his readers feel a greater amount of respect towards the black people.