Anyway, it was great. I'm breathless. Amazing to stand there in the middle of all those unthreatening bees and peer into their home. They've built a huge amount of comb in just seven days and it's absolutely perfect, pearl-white comb. I wish I had a photograph.
This is what the hive looked like after we replaced the cover:
I went out again a few minutes ago and it was almost completely back to normal -- just a bit of traffic at the entrance. Baking a loaf of banana bread suddenly seems incredibly dull.