Restoration of leather bindings

The restoration of leather bindings calls for much skill, experience, and a feeling for the past—without this last attribute the skill is largely wasted. Bad work often permanently ruins bindings and at best is likely to be costly to rectify so no structural restoration of important books should be attempted by untrained assistants or by professional restorers whose work is not known to be satisfactory. 

Middleton, B. C., The Restoration of Leather Bindings, American Library... 

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