For 38A I had no hesitation putting Ordnance Survey in for "OS in full" and after that eveything went chaotic. Sloppy clue! Also two typos in today's clues: In 3D "fro" instead of "for" was obvious, but I spent ages on trying to decipher "metal of glass" in 52A until I realised "of" was a typo for "or". Was this just me, or should we be giving this feedback to the Times compiler on behalf of quite a few of us?