The themes established on the east wall are continued on the west wall, where the technologies of the air (aviation) and water (shipping and pleasure boating) are represented. The half-face/half-skull in the central monochrome panel symbolizes both the coexistence of life and earth as well as humanity's spiritual and physical aspects, while the star symbolizes aspirations and hope for civilization. This heraldic image introduces another major theme of the cycle: the dual qualities of human beings, of nature, and of technology. On the same monochrome panel the city of Detroit, with the Rouge boat slip and a rubber tree plantation, representing the interdependence of the industrial north and agrarian south. Ore freighters, pleasure boats, and fish glide through the Detroit River in the center.

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