Sewing

The manuscript was resewn to the original marking up on double linen cord supports, and with thinner single cord supports for the kettle stitches (the point at which the thread leaves one quire and is taken to the next).  Parchment leaves of this weight are sewn with seaming twine, which is much heavier than the threads used for modern bookbinding.  The gauge of the twine is carefully selected to provide exactly the right amount of ‘swell’ in the quires so that the book takes on a natural round which will not collapse with use.  

Sewing is carried out on a traditional sewing frame which holds the cords taut. The sewing follows medieval and early modern examples of bookbinding in using a herringbone stitch.  In this style of sewing, the thread passes along the inside of each quire, exiting at the sewing hole between the pair of cords at that station.  A stitch is then worked around each of the two cords and pulled tight before the thread is passed back into the centre of the quire.  This process is repeated at every sewing station.  When subsequent quires are attached the same pattern is followed, but in addition to passing round both cords at each sewing station, the thread is passed under the stitch for the quire below before re-entering the quire being sewn.

Setting up a traditional frame on which to sew MS 251.
Sewing frames have been in use since at least the twelfth century.