598 Original Articles. [Oct.," 



the string is drawn aside, the whole string is removed from its 

 position of equilibrium, so that when it is released the vibration will 

 be chiefly confined to the string as a whole, that is, the fundamental 

 will far exceed in power the upper tones. If, on the contrary, the 

 string is struck by a hammer which springs away immediately, it is 

 only just that portion which was immediately in contact with the 

 hammer that is set in motion. 



Immediately after the blow, the other part of the string is at rest, 

 and is only disturbed by the wave which is set up at the point of 

 percussion, and which is propagated to the end of the string, and 

 reflected back again like a wave on a trough of water, producing a 

 long series of upper tones, the intensity of which may equal or even 

 surpass that of the fundamental. The harder and lighter the hammer, 

 the more quickly will it be thrown off, and the shorter will be the length 

 of string displaced at the moment of impact, so that the fundamental 

 might be quite inaudible, and the sound shrill, thin, and of disagree- 

 able quality. To obviate this, it has been found advantageous to 

 cover the hammers with soft felt. At the moment of first impact the 

 felt is compressed so that the force is gradually applied, and it is only 

 when a considerable length of the string is in motion that the 

 whole of the force has been expended and the hammer thrown off. 

 The thicker the felt and the heavier the hammer the longer will it 

 remain in contact with the string ; accordingly these conditions are 

 observed in the lower octaves of the pianoforte, where the strings are 

 long and heavy, and a proportionately greater mass must be set in 

 motion in order to get rid of the high upper tones which would spoil 

 the rich deep quality required. The time that the hammer is in 

 contact with the string, to a great extent regulates the upper tones 

 produced, for it is clear that there will be a tendency to produce just 

 those tones which require an excursion of the string in one direction 

 in the time, or in an even multiple of the time, that the hammer is 

 pressing the string in one direction. 



The place at which the blow is delivered exercises an important 

 influence in this respect, as none of those tones which have a node (or 

 place of rest) at this point can be produced. On the other hand, 

 those which have their maximum of oscillation about this point will 

 come prominently forward. Thus, if the string be struck exactly in 

 the middle, the fundamental which has its greatest amplitude here 

 will be most powerful, but the next octave will be wholly wanting the 

 12th, i.e. the 5th of the higher octave (the third tone) will be 

 prominent, but the 2nd octave will not be produced, that is, the tones 

 of the even numbers will be absent, but those of the uneven numbers 

 will be present. The ^effect of this is to give the sound a dull nasal 

 character. Now the first six tones come exactly into what is called 

 the major chord, that is, they are all thirds, fifths, and octaves, but 

 the seventh tone, which is a minor seventh, and the ninth, which is a 

 minor second, do not come into the chord. Theory, therefore, 

 indicates that the place at which the string should be struck is that at 

 which these tones have a node. Such a point is situated about the 

 seventh from the end of the string, and this is the place actually 



