Cold humming giant

I walked on white shiny ground. A giant white wall stood tall. It was humming. Low sound: mmmmmm. I stepped closer. Cold air came from underneath. I reached out one red hand to touch the metal side. It shivered against my palm, like tiny gears spinning inside. Then, a click. Sound stopped. I pulled hand back, scared. Did I break giant? I waited, very still. After quiet moments, a soft click came again, and the deep hum restarted. It is not broken. It breathes cold, then rests, like me.