The composition is somewhat free formed, loosely following the rule of thirds. Relying primarily on the interplay of other meaningful structure, specifically that of the sky, which appears subordinate but is ultimately the message.
The pier post is undoubtedly predominating and weighty, creating a heavy foundation to the rest of the scene. It is also a directional element, pointing upward, drawing attention towards the open sky. Once the eye is directed into this space, the slant of the clouds further accentuates a lofty and dynamic airiness, all underscored by the simple fact of ratio, in this case sky to ground. And so, we gain both contrast and harmony simultaneously, of which the poetry of the message follows.