=Wind Instruments: Vibrating Column of Air in a Tube=.—The next step in advance of noise-producing instruments is the discovery of means for the production of musical sound, which differs from noise in the possession of _definite pitch_. This leads to a consideration of the wind instruments that produce sound by means of a vibrating column of air enclosed in a tube. This is an important class and has several subdivisions, as will be seen. The simplest form of the wind instrument is the plain tube, producing a single sound when blown across the top. A series of such tubes fastened together side by side constitutes the _Syrinx_ or Pan’s pipe, an instrument known over all the world from the remotest ages. This is thought to be the instrument mentioned in Genesis with the Hebrew name _Ugab_—translated _organ_, in the verse: “Jubal was the father of all such as handle the harp or the organ.” It is generally believed by scholars that the =Pandean Pipe= or =Syrinx= is the oldest of musical instruments; but long before a sufficient advance had been made to bind together several reeds giving different sounds, the discovery was made that sound might be produced in this way. Some prehistoric man found it out, perhaps by blowing across the top of a hollow bone. A whistle of this kind, of prehistoric make, bored from one of the bones of a reindeer’s foot, was found in a bone cave in France. It may have been used as a signal, and we may imagine that it may have guided a troop of palæolithic hunters in the chase of the mammoth or rhinoceros, when these animals still roamed over the plains of Europe. =A Tube Pierced with Holes=.—The next advance was the discovery that one tube could be made to give several sounds by piercing holes in it. The effect of piercing is equivalent to shortening the tube; thus the =Flute= came into existence. There are three forms of the flute; the simplest is the old Japanese flute, blown at the end and pierced with a few holes. Next, the endless variety of flutes blown at a hole in the side, hence called the cross flute, or _Flauto Traverso_, in German, _Querflöte_. A perfect series of these flutes may be made. From the piece of bamboo with three or four holes, up to the exquisite workmanship and musical possibilities of the orchestral Boehm flute, all these flutes are identical in principle. The third kind of flute is blown at the end and is furnished with a diaphragm, which directs the air in a thin stream against the edge of the opening. Flutes of this kind were once used under the names of =flageolet= and =recorder=. Their chief interest lies in the fact that they have served as the model for the flue pipes of the organ, from the ponderous thirty-two foot Diapason to the half-inch extreme of the Mixture.