I wind about , and in and out , With here a blossom sailing ,

What is the meaning of sailing ? (here)

Skillful movement like that of smooth sailing of the ship has been described here with reference to the movement of the brook through the hills and valleys. It portrays a very hap-hazard or winding movement of the brook. Readers might also picture a snake wriggling when they read of this type of description of the brook's movement.