Historically, music was long classified as both art and science. Aspects of music -- from the mathematics of tuning to the music of the celestial spheres -- were primarily studied as science until the seventeenth century. In the nineteenth century, although scientists were less interested in the music of the spheres than the natural philosophers of earlier centuries, they remained committed to understanding the world of performing musicians and their instruments. In Harmonious Triads, Myles Jackson analyzes the relationship of physicists, musicians, and instrument makers in...