This set of four volumes of sheet music was bound by one of its previous owners and contains the instrumental parts for a variety of string quartet compositions written by variety of composers and published by different publishing houses between 1780 and 1809. 

The binding style of these four volumes is referred to as half leather. A book with all leather or all book cloth as its covering material is referred to as full leather or full cloth respectively. A book with leather or cloth at the spine and fore edge corners with an alternate material for the rest of the cover is half leather or half cloth. And, a book with leather or cloth just at the spine with a different material, such as cloth or paper, covering the remainder of the book is referred to as quarter leather or quarter cloth. (See images below) Quarter and Half bindings were developed as a way to minimize use of the more expensive binding materials by covering the rest of the book cover in a more economical material such as cloth or paper.

Three of the bound music scores were missing their spines and one had a detached spine. The leather was dry and brittle. In some cases, it had worn away to reveal the book board underneath. The paper sides, in this case blue paste paper, were also damaged and worn. 

The interior pages were mended with Japanese paper and wheat starch paste. The leather was treated with Klucel-G, a consolidant that also helps prevent the leather from burning (darkening) during the mending process as it is exposed to the moisture of the paste. The book board was consolidated as well, and in some cases it was rebuilt where it was too damaged or was missing parts.  

Japanese paper was applied over the exposed book board and toned with watercolor to more closely resemble the original covering material. A coat of Klucel-G was applied over the newly attached Japanese paper to further seal and protect it.

The new spines were created with Japanese paper laminated to Irish linen to lend strength, then attached to the books. The one remaining original spine was reattached over the laminated Japanese paper and Irish linen.

Not all of the books I treat receive full restoration such as these. Though I make every effort to create a tidy, attractive repair, the priority is usually the strength and speed of the repair. The amount of treatment is often decided between curator or client and conservator based on how an item may be used.