Master Nentray's Spreadings

A certain raven-haired boy lay on his bed, brooding over an absurdly large tome he had procured from the family library: Master Nentray's Complete Guide to Barriers and Wardings seemed very keen on upholding its promise of completion, as it held a staggering 12,000 pages. He carefully opened the formidable work and was surprised to find that what he had considered to be a fairly recent guide to protective charms turned out to be the unpublished magnum opus of a renowned charms master from the 18th century. With reverence, he turned the softly rustling vacat pages and stumbled upon a small handwritten note. The immaculate script in black ink read:

'Weight reduction and compression charms added at my personal leisure, along with a few private
A look towards the window told him that dawn was not far off. Still thinking about his new project, he mused that the only reason Nentray was not on some kind of black list was that he had apparently already grossed out the publisher, who had refused go public. Not that the tome contained any kind of malevolent magic, but the author seemed to take vindictive pleasure in describing the consequences suffered by would-be intruders. Harry was mostly interested in the deeper theory though, so the somewhat disturbingly graphic descriptions did not irk him. In fact, to Harry it seemed that Nentray had been an incredible genius and only failed to get recognition due to his somewhat vile personality. With one last look at his bedside table, he remembered the big envelope that resided well-hidden and deep within. Smiling to himself, he turned around, falling asleep within a few
'It's alright this one time. Do be careful though. That book is a unique.'
'A what?' Harry quickly blurted out before correcting himself. 'Sorry. What is a unique, Grandfather?'
'A unicum, Harry. I am quite sure neither the ministry nor Hogwarts has a transcribed copy.'
Harry was baffled. Usually Arcturus was quite strict where the library was concerned.
Apparently noticing the flabbergasted look on his grandson, Arcturus added, 'My own grandfather once told me how he was apprehended smuggling the very same book out of the library by his own grandsire. In any case, it is indeed a very good reference book and you will do well studying it. I had Cranky do a preservation charm on it, in any case. Please note that our rule still stands regarding any other book. Do we have an understanding?'
In spite of the reproof, Harry smiled brightly, 'Thank you, Grandfather.'
'It is quite alright. Why don't you show me some of what you have learned, and we can later talk about your understanding of the theory before our evening lesson?'
Harry's face was alight with excitement, 'I'd love that. Thanks!'
Seeing the smug look of his grandfather, he thought he could get away with what he had in