Less artistic analysis, more the colorful history of a provenance, “Botticelli’s Secret” offers short, vivid biographies of Dante and Botticelli before embarking on a tour of the turbulent fate of the latter’s Divine Comedy sketches, a tour which also functions as an examination of the fluctuating artistic tastes of recent centuries. Most interesting for its demonstration of the link between Botticelli’s modern vogue and his appeal to both sides of the Victorian “Medieval vs. Renaissance” debate. — Elijah Blumov