Hidden in Plain Sight: Musical Treasures in the Penn Library Curated by Marjorie Hassen Otto E. Albrecht Music Library University of Pennsylvania

Harmonicorum libri XII Marin Mersenne, 1588-1648 Harmonicorum libri XII Paris, 1648 Folio FC 6 M5553 635h 1648 The mathematician and philosopher credited with, among other accomplishments, the formulation of the physical laws governing the vibration of strings, Mersenne was a prominent speculative theorist of the 17th century. His interest in music was primarily a result of his work in mathematics and physics, particularly evident in the last four books of the Harmonicorum libri, which form a treatise on musical instruments.

Table of Contents Introduction Manuscript Collections: Institutions Manuscript Collections: Individuals Sheet Music Images Conducting Scores Music Manuscripts: 15th-18th Centuries Music Manuscripts: 19th & 20th Centuries Landmarks of Music Theory