If the cords project above the spine after sewing they are hammered into the grooves during backing. Books sewn in this manner may have hollow or tight backs; in the case of the hollow back, the purpose of sewing not to show apparently is to prevent creasing of the leather of the spine by the cords, while attempting to retain the strength of genuine flexible sewing. In the case of the tight back, the purpose is to have a smooth spine and a book with sewing that is stronger than is possible withRECESSED-CORD SEWING ; however, in this case, most of the desired benefits are negated because of the need to make the cords extremely thin. (236 , 371 )
![[CoOL]](/icons/sm_cool.gif){kind=icon}