"Two of Leonardo's notebooks, having been officially lost since 1830, were rediscovered in the Biblioteca Nacional, Madrid, in 1965... On the basis of the wealth of new material in the notebooks, a group of the world's leading Vincians contributed to a reassessment of the many facets of Leonardo's genius, a large-scale collection of essays, which was published as The Unknown Leonardo. The present book...is reprinted in smaller format from that voluminous work"--from Introduction (page 7)
