_Taste_ is the next sensation of the nerves, regarding an immediate approach and action of substances themselves, in order to distinguish betwixt the nature of foods, by which we are enabled to form an idea of _salt_, _sweet_, _sour_, _bitter_, _sharp_, or _mild_; which according to their mixture and proportion, render _taste_ agreeable or disagreeable. Its seat is principally in the tongue; but that it extends to the very stomach itself, is evident, from the immediate consent of parts; namely, that what is disagreeable to the palate, will ever be nauseous to the stomach: Of which I shall say more hereafter. _Smelling_ is that sensation given to the animal creation, as a friendly messenger of taste, in order to enable us the better to chuse our food. It is actuated by means of the _olfactory nerves_ spread in the _pituitary membrane_ of the nose, and has an immediate communication with the brain; which nervous plexus is actuated by odorous particles, exhaling from substances, by which the olfactory nerves are stimulated agreeably, or disagreeably, as the first intelligence to the palate, or to the whole consent of the nervous system. _Hearing_ is that sensation of the nerves which is occasioned by the vibration of the air, and forms the sound, which enters the cavity of the ear, and tremulates and puts in action, the organs of hearing. The ear is perhaps as curious a piece of mechanism to our conception, as any part whatever we shall meet with in anatomy. To the organs of hearing we must reckon the external and internal _auditory_, divided by a thin membrane, which is a thin spreading of nerves, called the _drum_; within this, or in the internal cavity, we observe, 1st. Four little bones called, from their forms, the hammer, _malleus_; the anvil, _ancus_; the stirrup, _stapes_; and roundling, _orbicularis_. 2dly. Their peculiar muscles. And, 3dly. Two considerable cavities, the _labyrinth_ and _aqueduct_. How hearing is actually brought about, Anatomists have not as yet agreed; and which would be too tedious here to enquire into. That the little hammer is perpetually moving on the _tympanum_, according to the different sounds, may be one part; which, however, is greatly assisted by the other organs. The _labyrinth_, with many turnings and windings, penetrates through the skull and forms part of the aqueduct, by which the sound is modulated and magnified, so as to cause the distinction between them, and convey the idea of their sonorousness to the common receptacle of sensation.