X CONTENTS. CHAPTER III. ON RESONANCE. Resonating pianoforte wires and tuning-forks ; cause of the phenomenon, §§ 37, 38—Resonance of a column of air ; laws of its production, § 39—Relation between the length of an air- column and the pitch of its note of maximum resonance, § 40— Resonance-boxes, § 41—Helmholtz’s resonators, § 42. CHAPTER IV. ON QUALITY. Composite nature of musical sounds in general ; series of con¬ stituent tones, and law which connects them, § 43—Experimental analysis of musical sounds, §§ 44, 45—Nomenclature of the sub¬ ject, § 46—Helmholtz’s theory of musical quality, as depending on the number, orders, and relative intensities of the partial-tones present in any given clang, § 47. CHAPTER V. ON THE ESSENTIAL MECHANISM OF THE PRINCIPAL MUSICAL INSTRU¬ MENTS, CONSIDERED IN REFERENCE TO QUALITY. Sounds of tuning-forks, § 48—Modes of vibration of an elastic tube, § 49—Meeting of equal and opposite pulses ; formation of nodes, § 50—Number of nodes formed, § 51—Nature and rate of segmental vibration, §§ 52, 53—Motion of a sounding string; quality and pitch of its note, §§ 54, 55—The pianoforte, § 56— Meeting of equal and opposite systems of longitudinal waves, § 57—Reflection of Sound at a closed and at an open orifice, § 58—Modes of segmental vibration in stopped and open pipes, §§ 59, 60—Deepest note obtainable from a pipe, § 61—Relation between length of pipe and pitch of note, § 62—Theory of re¬ sonance-boxes, § 63—Flue-pipes and reed-pipes, § 64—Construc¬ tion of flue-pipes and quality of their sounds, § 65—Mechanism of a reed ; timbre of an independent reed, and of a reed associated with a pipe, § 66—Orchestral wind-instruments, § 67—Mechan¬ ism of the human voice, § 68—Synthetic confirmation of Helm¬ holtz’s theory of quality, § 69.