A. M. Mayer—Researches in Acoustics. 175 
iece of wax, so that it gave five beats per second with the 
note of the fork when unloaded, I could not, by any variation 
in the tension of the fiber or of any other circumstances of the 
experiment, set in vibration the fork by means of the pulses 
sent from the reed through the fiber; yet, on placing the nipple 
of an Ut, resonator in my ear, I perceived that this flattened 
note of the fork produced a decided resonance, thus showing 
that although the fork could not respond to its own note 
flattened five beats per second, yet the resonator, under the same 
circumstances, did enter into sympathetic vibration. When the 
fork gave four beats per second it responded to the reed, but 
this response was only audible on placing the ear close to the 
mouth of the fork’s resonant box. With three beats per second 
the sound of the fork was readily perceptible, while the resona- 
tor reinforced it very decidedly. When the fork was out of 
unison two beats per second, its sound was slightly increased ; 
and with a departure of one beat per second, the response of the 
fork was yet stronger, but greatly inferior in intensity to that 
produced when the fork was in unison with its proper sound— 
the second harmonic of the reed; yet the resonator reinforces 
this flattened sound as forcibly as it does that which emanates 
m the unloaded fork. These facts concerning the want of 
sharpness in the detection of pitch by means of resonators are 
not in accordance with the statements made in recent popular 
works on sound, where the resonator is described as remaining 
dumb until the exact pitch to which it is tuned is reached, when 
it responds with a suddenness which has been com to an 
explosion 
unison with the second harmonic of the was evident in the 
difference in the intensities of the fork’s responses when thus 
oaded and when the wax was remov This fact I have 
repeatedly confirmed by testing the intensities of the two 
sounds ns different hearers, who ples placed so that they could 
not see when the fork was loaded or unloaded. Now E. H. 
Weber has found that only the most accomplished musical ears 
can distinguish between the pitch of two notes whose vibrations 
are as 1000 to 1001, but by the above method we can readily 
detect a departure from unison in the two notes amounting to 
the interval of 2000 to 2001, or to the ;},th of a semitone. 
