We seemed to be standing perfectly still, without any motion of any sort except a tiny teetering motion of the hamper-basket, while the earth and what was on it fell rapidly away from beneath us.

At once all sense of perspective became distorted.
When on the roof of a tall building this distortion had never seemed to me so great.

I imagine this is because the building remains stationary and a balloon moves.

Almost directly below us was one of our party, wearing a soft hat with a flattish brim.

It appeared to me that almost instantly his shoulders and body and legs vanished.