A practical Treatise on Wireless Telegraphy and Telephony, giving Complete and Detailed Explanations of the Theory and Practice of Modern Radio Apparatus and its Present Day Applications, together with a chapter on the possibilities of its Future Development
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WIRELESS TELEGRAPHY
he membraneous lining on which the ultimate ends of
t e nerves are spread is virtually a sensitive beach, and the
little otoconia, showers of pebbles and sand, which are
raised and let fall by each succeeding wavelet of sound.
This wonderful mechanism constitutes the inner ear.
The ear, as a whole, consists of three parts: the outer
ear, which is a trumpet-shaped passageway called the pinna
serving to collect the sound waves and pass them on through
rHAMM£R
Fig. 12i.—The ossicles.
the auditory canal to a small membrane called the ear-
drum; the ossicles, a series of three little bones, the ham-
mer, the anvil, and the stirrup, they are called; and the
inner ear just described.
The foot of the stirrup is connected with an oval mem-
brane, which closes a hole in the inner ear. Sounds pass-
ing through the auditory canal cause the drum to vibrate
and send tremors through the bones to the liquid in the
little sacs. The tumbling of the “pebbles” against the fila-
ments of the auditory nerve sends the intelligence to the
brain.
The impression which the mind receives through the
organ of hearing is called sound. All bodies which pro-
duce sounds are in a state of vibration, and they communi-