The song itself had hinges. 
The clasp on the eighteenth-century Bible 
had hinges, which creaked; 
when you released the catch, 
the book would sigh and expand.  The song was of two wholes 
joined by hinges, 
and I was worried about the joining, 
the spaces in between
  the joints, the weight of each 
side straining them.
~Saskia Hamilton~