Sentence:  For instance, you take the uncompleted books of living authors, fresh from their hands, wet from the press, cut, hack, and carve them to the powers and capacities of your actors, and the capability of your theatres, finish unfinished works, hastily and crudely <WSD>vamp</WSD> up ideas not yet worked out by their original projector, but which have doubtless cost him many thoughtful days and sleepless nights; ... 
Meaning of the word marked with <WSD> tags:  "Often as" '''(vamp up)''': to fabricate or put together (something) from existing material, or by adding new material to something existing.