250 A. M. Mayer—Researches in Acoustics. 
responding co-vibrating parts in the inner ear, differences of 
pitch should be difficult, even impossible, to distinguish, and 
this we find to be the case. 
The fact that the durations of the residual sensations dimin- 
ish, as the numbers of vibrati 
s 
tions, outside the ear, have ceased ; for from that instant the 
residual sensation becomes more and more simple in its char- 
acter, until at last only the simple sound of the fundamental 
oni¢ remains in the ear, oR soon after, this sensation also 
vanishes. Thus, after the vibrations of an UT, reed pipe con- 
taining twenty harmonies have ceased, the residual sensation of 
the twentieth harmonic, or that highest in pitch, disappears in 
the 53, of a second; but the sensation of the fundamental, or 
lowest onic, remains in the ear ;'s of a second after the 
sensation of the highest has vanished ; and the fundamental 
remains ;'; of a second after the cessation of the sensation of 
€ successive rates of increase of the ordinates of the curve 
