* "Wind about" implies a winding, twisting movement, like a snake or a river.
* "In and out" further emphasizes the brook's constantly changing direction, moving between banks and around obstacles.
The phrase reflects the brook's natural flow and unpredictability. It also suggests a sense of freedom and vitality, as the brook isn't confined to a straight path but moves freely through the landscape.
This imagery is reinforced by other lines in the poem, like:
* "You dance along with the little breeze"
* "And ever the flitting swallows' wings"
* "And the whispering reeds"
All of these lines contribute to the poem's overall sense of the brook's lively and constantly shifting nature.