The Eardrum.-on the back of this flap is seeing a strikingly natural representation of the middle ear, the tympanum or drum, as it is frequently called. For the bottom of the tympanum is observed the Eustachian tube, through which is conveyed air from the pharynx to the middle ear. Across this chamber is seen stretched three very tiny, Cingular phones, which, from their shape, or called a hammer, the ample and the states. These delicate bones are connected together, one by ball and socket joint, the other by a hinge joint and by ligaments, and are moved by small muscles; they serve to convey the wave sounds across the tympanum cavity to the internal a year.

There is that crazy word again, tympanum.  In architecture, I believe that refers to an arch or an arch system.  I have a feeling the author looked it up and couldn’t stop using it, like some desperately needing addiction treatment repeats a phrase over and over again without any rhyme nor reason.