"lonelytraveller" wrote in
message
...

So either they've built a huge expensive glossy wall, just before they
need to demolish part of it, or the wall somehow has the ability to
easily vanish, without drilling.

So what's going on with the wall?

Found this picture of the works at Blackfriars, since posting the earlier
reply, which may be relevant to this. Shows how a fairly solid looking
stone wall can be fabricated. No guarantees that the wall at Farringdon is
exactly the same but it seems quite possible:

http://www.flickr.com/photos/ianvisi...n/photostream/

Paul S