Upon the application of the bellows to supply wind, instead of the human lungs, the fingers were used to stop the pipes, and thus prevent their sounding all at once, which it is evident they would have done, standing on a simple wind-chest, which was filled by the bellows. As the number of pipes was gradually increased, the difficulty of managing them by hand of course became greater and greater. This in time led to the invention of the pallet, or valve, to control the admission of wind to each pipe, and by the close of the eleventh century we find it chronicled that there existed at Magdeburg an organ with a _key-board_ comprising sixteen keys. From this time the name of the instrument begins to correspond with our modern idea of the same; its invention was a realized fact, although but a germ of that development which has since raised organ-building to its artistic importance. It must be borne in mind that the pedal organ, with its keys for the feet, was a much later invention. Meantime, the first keys made use of measured from three to five inches and a half wide. Consequently, the title of the performer on this instrument, in the eleventh century, was not that of organ-_player_, but organ-_beater_, the keys being struck by the fist, which was protected by a heavy glove. There was, it must be remembered, but one rank of pipes, and these could seldom, if ever, have been in tune, from the fact that they had no means of regulating the wind pressure; while in organs of later date, and at the present day, an even wind is secured principally by weights placed upon the bellows, and the creation of a reservoir of compressed air. At this early time the wind supply was furnished by the common bellows as used by blacksmiths. Thus the supply and consequent pressure of the wind would necessarily be in direct proportion to the muscle or activity of the blowers.