In 1644, Evangelista Toricelli wrote, “We live submerged at the bottom of an ocean of air.” We don’t feel the force of the pressure of this fluid any more than aquatic creatures feel the force of the water on all sides. Why? Because there is a uniformity of pressure in both cases; gravity exerts pressure on all sides.
Imagine for a moment that everything on the Earth and above its surface could exist under the water, or vice versa, without any change in appearance or properties. If we visualize horizontal bands atop one another, it would break the habitable area into observable layers. Grass, trees, plants, insects, ground-dwelling animals would all be in the same layer as the plants, crabs, bottom-feeders, and sand dwelling creatures beneath the surface of the ocean. There would be fish swimming in the layer above our heads with the birds. Airplanes would soar further above, in a layer with the whales. Dolphins would escape the surface of the ocean, accompanied by rockets, at the topmost layer above Earth. It would be a jumbled and magnificent scene. Wait! There’s more!