Music is not an isolated fact, it is bound up with the lives, with the daily routine of peoples and nations; its courses of development, cannot rightly be judged apart from geography, ethnography, archæology and history. In the early migrations man’s music went with him as his language went, his simple instruments he could fashion by the wayside, and in later eras as men advanced, a craft would organize itself, determining the progress of the instruments from a rude to a refined style of construction; thus a kind of Art would be confirmed and thereout a system of music would arise, which to the people of the time, at whatever stage of attainment considered, would be as mature to them as our present system is to us. The structure of the instruments defines the possibilities of the music, and my belief is that a true idea of the character of ancient musical display can only be arrived at through a practical knowledge of such structure, its capabilities, its limitations, and the scope of its technique, since the qualities of tone that are at the command of the player are always determined by the means of excitation of the sounds, and by the shape and interior forms of the instruments. The ancients had no system of harmony, yet there must have been harmony in the air, a promiscuous harmony arising through the variations in a multitude of unisonous effects. A study of the Double Flutes, the Greek _Auloi_, has led me to some original conclusions which may or may not be corroborated by future discoveries, and I read with eager hopes of a projected International scheme for the complete excavation of the buried city of Herculanæum, just announced, which, if carried out, may reveal many things that we want to know concerning these mysterious instruments. Throughout a long life I have been occupied with books and with music, especially with the instruments that make the music, their construction and scientific bearings and relations, practically and experimentally, and thus it has happened that many advantages seldom combined have favoured the pursuit of the investigations discursively related in the present volume. My thanks are due to Messrs. Cassell and Co., who kindly supplied several blocks, illustrating the Egyptian and Assyrian sections, used by them in Nauman’s “History of Music,” and Dr. J. Stainer’s “Music of the Bible.” To the Secretary of the Hellenic Society, Mr. J. Penoyre Baker, I am indebted for the photograph of the Apollo of Praxiteles brought by him from Athens, which I use for the frontispiece.