21/07/14: Music down the drain, Hutton Grove, Finchley, N12

What's left of the text suggests something to do with "Philadelphia". But did this TDK disc's contents relate to the city in Pennsylvania, the 1993 film starring Tom Hanks and Denzel Washington, or the cream cheese? Unlikely to play.

09/07/14: Clear disc near Regent's Park

Strictly speaking, not a CD. It's one of those transparent circles that sits at the top of a CD-R spindle.