In the third paragraph of Xiaoshitang Book, when writing about the source and flow direction of the stream, what characteristics of the stream body and shore potential are described in turn? What rhet

In the third paragraph of Xiaoshitang Book, when writing about the source and flow direction of the stream, what characteristics of the stream body and shore potential are described in turn? What rhetorical devices are used? Looking from the southwest of the pool, you can see that it is zigzag. Their shore potentials are different from each other and their sources are unknown.

Looking southwest of the pool, I saw the stream winding like the Big Dipper, winding like a snake, flickering. The bank of the stream is as uneven as a dog's teeth, and I don't know where its source is.

Characteristics of river bending and expansion.

Characteristics of uneven shore potential.

A figure of speech is used.