My favourite activity is to touch, smell, and listen to the crackling sound of cows and sheep that have been dead for a thousand years. That’s right, I am talking about medieval parchment, the standard material for books made between the fifth and thirteenth centuries. Animal skin replaced papyrus (standard up to the fifth century) and would ultimately be challenged by paper, which competed for dominance during the later medieval period. Parchment was resilient, however, and it was even used by early printers, including Gutenberg himself – showing the use of animal skin did not die with the medieval manuscript.

There is a lot you can tell from medieval skin. Like a physician today, the book historian can make a diagnosis by observing it carefully. The best quality, for example, feels just like velvet. It usually has an even, off-white colour, and it makes no sound when you turn the page. Bad skin, by contrast, crackles. It is of uneven thickness, and shows staining…