October Challenge - Black and White

Day 7 of DDW's October daily challenge - Black and White

Last week the hoardings around the building site at the end of Chiswick Park suddenly grew a few decorations, in the form of puzzles and other things. While they are in fact in black and yellow (everything that doesn't move gets painted yellow there) it was a simple task to convert this to black and white.

So what do you see?