The determination of the _direction_ of sound is a problem of acoustics.
Some have contended that the arrangement of the semi-circular canals is
in some way connected with this sensation. But this supposition,
together with the theory of the transmission of sound through the
various portions of the cranial bones, has been exploded.

From the foregoing description, it will be seen that the labyrinth and
tympanum are the most essential parts of the organs of hearing. In
delicacy and refinement this sense ranks next to sight. The emotions of
beauty and sublimity, excited by the warbling of birds and the roll of
thunder, are scarcely distinguishable from the intense emotions arising
from sight. It is a remarkable fact, that the refinement or cultivation
of these senses is always found associated. Those nations which furnish
the best artists, or have the highest appreciation of painting and
sculpture, produce the most skillful musicians, those who reduce music
to a science.


SMELL.


[Illustration: Fig. 65.
1. Frontal sinus. 2. Nasal bone. 3. Olfactory
ganglion and nerves. 4. Nasal branch
of the fifth pair. 5. Spheno-palatine ganglion.
6. Soft palate. 7. Hard palate, _a_.
Cerebrum, _b_. Anterior lobes, _c_. Corpus
callosum. _d_. Septum lucidum. _f_. Fornix.
_g_. Thalami optici. _h_. Corpora striata.]