sound in the instrument, so, in the same manner, circumstances, which affect the tension and relaxation of the tympanum, vary most perceptibly its powers of action, and the customary agency of the organ.  Its four bones act mechanically, in consequence of the power of the local muscles:  they strike like the key of an instrument, and produce a percussion on the nerves of the tympanum.  Not only may the membrane of the tympanum be partially destroyed, and hearing be preserved, but the small bones of the tympanum have been in certain cases lost, or have come away, from ulceration, and through a constitutional or other cause; but in such cases it appears that the stapes was, in most instances, left, and thus the openings of the fenestra ovata and fenestra rotunda were preserved, which prevented the escape of sound from the labyrinth and internal parts.  With respect to the Eustachian tube, its aperture into the throat seems indispensable to hearing; and whenever closed, from malconfirmation or disease, deafness is the certain consequence.

The third division of the organ is the internal ear, which is called the labyrinth; it is divided into the vestibule, three semicircular canals, and the cochlea:  the whole are incased within the petrous portion of the temporal bone.  The internal ear may be considered as the actual seat of the organ; it consists of a nervous expansion of high sensibility, the sentient extremities of which spread in every direction, and in the most minute manner; inosculating with each other, and forming plexus, by which the auricular sense is increased.  Here, also, sound is collected and retained by the mastoid cells and cochlea.  To this apparatus is added the presence of a fluid, contained in sacs and membranes; as this fluid is in large quantities in some animals, there is no doubt it is intended as an additional means for enforcing the impression:  the known influence of water, as a powerful medium or conductor of sound, strengthens this idea.  The internal ear of man, therefore, has all the known varieties of apparatus, which are only partially present in other classes of the creation; and its perfection is best judged of, by considering the variety or form of the internal ear of other animals.  The internal ear of some animals consists of little more than a sac of fluid, on which is expanded a small nervous pulp; according to the situation of this, whether the creature lives in water, or is partially exposed to the air, it has an external opening with the ear, or otherwise.—­Lecture delivered at the Royal Institution, May 30, 1828—­by J.H.  Curtis, Esq.

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THE GATHERER.

A snapper up of unconsidered trifles. 
SHAKSPEARE.

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POETICAL WILL

Of Nathaniel Lloyd, Esq.  Twickenham, Middlesex.