Post by Graeme Wall Post by Basil Jet
This is nowhere near the Crossrail alignment, BTW.
Standard OS survey?
I don't think so. They seem very interested in one particular building.
The Secchi disk-like fiducial markers are stuck on with masking tape,
which means they are expecting movement in the space of a few hours...
the retroreflectors used for monitoring movement during the Crossrail
project were all screwed on so that movement over several weeks could be
monitored. I imagine they were enlarging a cellar, but the whole thing
looks a bit ramshackle with fiducial markers blowing in the wind and
theodolites prone to being knocked by a dog or pigeon.
Basil Jet recently enjoyed listening to
Soft Machine - 1971 - Fourth