two small applications of science

One:
The sky has been such amazing colours this week - every night, orange, as the lights are reflected back to us off the clouds. Tonight the clouds don't cover the whole sky. There's a band of plain air near the horizon (such as it is; the city horizon, I mean) which, in contrast to the orange, looks a thin green.

Two:
It occurs to me, I spend my whole life on upper floors: I live on the 2nd floor, and work on the 1st (that is, 3rd and 2nd if you're American). At my desk I'm constantly feeling some sort of weird vibration somewhere under me, which has the strange effect of making me feel jittery, as if it was coming from me; no idea what it is. But I suddenly realise I'm never anywhere near the ground unless I'm out. The doll's house was just rattling, I could hear its tiny little objects rattling around inside it. A doll ghost?? So exciting! I even opened it up to have a look, but the rattling continued - only slightly less, with my hand on it, absorbing some of the vibrations. Then I realised it must be the washing machine in the flat below, on spin.