T EL B 
AMERICAN NATURALIST. 
Vol. VIII.— OCTOBER, 1874. — No. 10. 
ec eTR TD 
EXPERIMENTS ON THE SUPPOSED AUDITORY 
APPARATUS OF THE MOSQUITO.* 
BY PROF. A. M. MAYER. 
Oum states in his proposition that the ear experiences a simple 
sound only when it receives a pendulum-vibration, and that it de- 
composes any other periodic motion of the air into a series of pen- 
dulum-vibrations, to each of which corresponds the sensation of 
asimple sound. Helmholtz, fully persuaded of the truth of this 
Proposition, and seeing its intimate connection with the theorem 
of Fourier, reasoned that there must be a cause for it in the very 
dynamic constitution of the ear; and the previous discovery by 
the Marquis of Corti of several thousandt rods of graded sizes in 
the ductus cochlearis indicated to Helmholtz that these were suit- 
able bodies to effect the decomposition of a composite sonorous 
wave by their co-vibrating with its simple harmonic elements. 
This supposed function of the Corti organ gave a rational expla- 
eee ORieh TS ic EC Ter ae 
ted, a few corrections by the author, from the American Journal of 
and Arts, Aug., 1874. 
t“ But rhe theory of consonance and 
ts solely on a minute nals of the sensations 0 This analy- 
sis could S been made by any cultivated ear, without the dof veh Des but the 
of pans se the saclay’ of appropriate m observation, 
ary degree. 
Meg felted i in an 
oe org organs of coe gly no immediate relation with the paces er of PAEA 
monics which rests keem on the facts of observation, on the beats o 
and of resultant sounds.” — Helmholtz, Tonempfindungen, p. 342. 
SS AEDST RARESA 
vibration 
10I SMOUN 
Somn eered, according to Act of Co gress, i be the year 1874, by the PEABODY ACADEMY OF 
in the Office of the poorest of Co a on reins 
AMER. NATURALIST, V (577) 
