How to calculate along lines - Rechenbuch (part 1)
A Rechenbuch is a kind of calculating manual, dating from medieval or renaissance times...
This book is a reprint of one of Adam Ries works "Rechenbuch auff Linnien", printed as a follow-up edition in 1578. Although the original text is from the middle of the 16th century, the cover should look like a simple no-nonsens binding from the 15th century. Sturdy, practical, not too expensive - the right thing for a clerk around 1476 who would have need of such a Rechenbuch.
I started by discarding the modern book cover and taking apart the modern binding. After that, the book was just a little heap of pages, folded and stacked into sections. Now I could start again, just as if it had recently come from the press :-)
The binding and cover will follow the technique and design of this little book: Ephraem Syrus: Sermones from the 15th century, a small volume with wooden boards and a simple leather cover. It measures 14,5 by 10 cm and has 99 leafs.
The Rechenbuch is 16 by 10,5cm and has 114 pages, so not exactly the same, but very similar in format.
I used 5 raised bands cut from chamois leather just like on the Sermones, which is quiete a lot for a book that small. I think the medieval bookbinder wanted to make really sure this binding would last - well, it did for almost 500 years :-)
Above you can see the sewing over the raised bands, the spine has been glued for the first time and is ready to have the headbands sewn on.
As the book is so slim, I needed the help of two turned wooden jars I use to store dryed glue and polishing chalk to make it stand up. Again I'm amazed about the beauty simple things like tools or containers have, when they are handmade!
To the right you can see the book lying on a small book bag with tassels, handwoven from madder and tansy dyed wool. Another lovely little detail that makes medieval bookbinding such fun :-)
Speaking about little details - here`s a preview of the brass clasps and mounts that will decorate the leather cover:
The clasp is still burnished as it was produced to replace a missing clasp on an original medieval book during restoration. I gladly use these replicas, but I polish them before use till they gleam.
The little semipherical mounts will be on the front and back cover near the corners, they prevent the leather from contact with the table or bookshelve surface.
When you look closely on the cover of the Sermones, you can still see the tiny holes in the leather left by the long gone mounts...
Enough for today, I`ll keep you posted :-)