I can now do what I said at the end of that post ("I will have to revisit the post in a few years when the book is safely written and published and it will make rather a nice story, I think.").
So, here's that cryptic paragraph, with all the details for Magpie Hall inserted.
"While waiting for the order to arrive, I had the brainwave for my new novel, in no way related in subject matter to the five books I had just ordered. My protagonist (ROSEMARY) has a specific occupation (TAXIDERMIST) and in the novel, a certain object that I had never heard of before until very recently (A CABINET OF CURIOSITIES) plays a big part in the story. So the Amazon package arrives and I am happily reading the first novel when unexpectedly, what should turn up, unannounced, but a CABINET OF CURIOSITIES. The book delves right into the history of CABINETS OF CURIOSITIES and gives many prime and beautiful examples. That book finished, yesterday I randomly picked up the second in the pile of books and lo and behold the first page has the main character STUFFING THINGS. He is a TAXIDERMIST."