Flight changing at higher altitudes

I flew straight up.

The tallest rooftops downtown were left below me. The air got colder and the precipitation more ferocious as I rose up higher, and if I had any trouble breathing, I wasn't sure how much of it was my cold constricting nasal passages, and how much was the thinner air.

My eyes closed, fists clenched, I slowed my ascent. I continued upwards, more gentle now.

I could feel the transition. My flight was like an ice cube, sliding across a slick floor. If there was any resistance, it was in the air. But up here, the air was thinner. I panted for each breath.

Maybe it was how pure things were up here, now small the problems below were, how there was little to see except the diffuse clouds that made it impossible to see twenty feet away from me. There was no noise up here, except the wind against my hood and the bottom end of my coat.

Maybe it was that the air was thinner, so there was more room to feel other things.

I could feel distinctions. The ice cube slide of flight became smoother still. It was a slide over skin, not scar tissue. No bumps, no tiny bits of turbulence that weren't actually wind. If I controlled fire and paid the most acute attention, would I see the difference in how the flames touched and tongued the air? If I mutated from head to toe, would it shape my form, the whorls of metaphorical fingerprints, and the spacing of pores?

- From Within 16.4