The importance of this subject, whatever the value of the work of any individual observer may be, must be manifest to all, for upon a right understanding of it depends the power of designing buildings of good acoustical proportions and wind instruments of all kinds, and the massing together to the greatest advantage (or perhaps we should say the least disadvantage) of large numbers of singers and instrumentalists. In the highest regions of physical science, also, the determination of the velocity of sound has had its place, not only for its own sake, but as a means to an end of great importance. However, it will not be necessary for our purpose to do more than touch upon this point.