Page:Cyclopaedia, Chambers - Volume 2.djvu/277

 NER

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NER

there tallM Proceffiis Fafillares, which Dr. Drake takes to into two ; the upper whereof is diftributed by many Twia§ be a properer Name in that Place, than that of Nerves ; into the Membrana Pituitaria. The lower, paffing a pe- they appearing rather Productions of the Medulla Oblongata, culiar Hole on the hind and lateral part of the Bone of the whence the Olfallory Nerves arife, than diftinft Nerves. As Palate, is distributed into that fpongy Flefh that lines the foon as they have made their way thro theOJCnfo-o/am.they Palate, and the tough Membrane that covers it. are diftributed throughout the Membranes of the Nofe. The third little Branch is fpent on that part of the Their Ufe is in the Senfation of Smelling. See Smelling. Membrana Pituharia that lines the Fauces upon the Uvula

O/kNerves. Thefe pafs the Skull thro two Perfora- and Mufdes thereabouts, and upon the Tonfils. tjons in its Balis, a little above the Sella Eauina, and are The greater or foflerior Branch, after fending a few thence convey'd to the Tunics of the Eye 5 whereof, the Twigs to the Sara Mater, paffes the Skull thro the fifth Retina, fuppofed to receive the Objects of Vifion, is an Foramen ; and having fent off fome Twigs to the Buccinator Extenfion of the inner or medullary part alone. SeeVi- Maffeter, and the Mufcles of the lower Jaw, is divided into sion and Retina. three considerable Branches.

Nerves that move the Eyes, Oculorum Motorii, arife from The firft paffes to the Root of the Tongue, and thence the Crura of the Medulla Oblongata, near the Annular Protu- proceeding forwards, fends feveral Branches to the Maxil- berance ; whence they march out between two Branches lary Glands. It fends others along the inner Subilance of of the Cervical Artery; and paflingout of the Skull at an the Tongue, which end in Capillaries at its Extremity, and irregular oblong hole, immediately under the former, are joining every where with the Branches of the ninth Pair fpent on thufe Mufcles of the Eyes call'd Attollent, Defri- ferve both the Mufcles and Papillary Glands, and contri- ment, Adducent, and Ohl'tauut inferior ; except fome fmall bute to the Tafte, as well as the Motion of the Tongue. Fibres fpent in the Mufcles of the upper Falpebra. See Eye. The fecond, or middle Branch, after diftributing a Twie Patheuc Nerves, arife behind the Tejtes, and paffing into the Maxillary Glands, and the Mufcles Stylclojfus and out of the Skull at the fame Foramen with the former Myloglojfus, enters the hollow of the lower Jaw, along w'hich Pair, fpend themfelves wholly on the Trochlear Mufcle. it runs accompanied with Branches of the Carotid Arteries Fifth Pair of Nsrves, the largeft of all thofe coming and little Veins, which return to the internal Jugulars 5 from the Brain, has its ufe as well as distribution more and befides fending off a Twig to each Tooth, with the extenfive ; fetving both for Senfe and Motion, for Touch Membranes of the forcfaid Veffels, contributes to form a and Tafte. It fends Branches not only to the Eyes, Nofe, Membrane which lines the whole Sinus. At the fourth Palate, Tongue, Teeth, and moft parts of the Mouth and Grinder it divides into two ; the lefs whereof runs to the Face, but alfo to the Breaft, lower Venter, Procardia, \$c. joining of the Jaw; the bigger, paffing out at a peculiar by means of the Intercoftals, which are partly compofed Perforation, is divided into feveral Fibres, which are dif- ot Branches of this Nerve ; whence atifes a Content or Sym- pofed into the Mufcles of the lower Lip and Chin, pathy between the feveral Parts of the Body. SeeCoN- Thetiirrfor exterior Branch, is fpent on the parotid Glands. sent of Farts. Sixth Pair of Nerves, or the Guflatorii, rife from the Me-

lt arifes from the Annular Protuberance, near the Pro- dullary Tracts of the Centrum Ovale, below the annulat eeffus Cerebelli, and is at its Origin very large, but before Proccfs, and ptoceeding forwards, enters the fame Recep- its egrefs from the Dura Mater is divided into two Branches, tacle, or Sinus of the Skull, on the fide of the Sella as the each cunlifting of innumerable nervous Fibres, whereof fifth Pair does j whence fending off a Twig to join thofe of thofe of one Branch are pretty tough and firm ; the other the fifth Pair, in their paffage to the Intercoftals it goes foft and lax. A little beyond the Sella, it forms a Plexus out ot the Skull at the fame Hole with the Moto'is Oculo- call'd Ganglioformis, near which, each Nerve is divided into rum, and ends in the abducent Mufcles of the Eye • fending an interior mafofteriw Branch. withal fome Twigs to the Tongue. See Tongue!

The Anterior or Fore-Branch, after a few Twigs fent to The Seventh Pair, or Auditory Nerves, arifing from the the Dura Mater, enters the Receptacle on each fide the medullary Traft of the fourth Ventricle, and paffing out of Sella ; whence it fends off one or two Twigs to the Inter- the Skull thro a Hole of the Os Petrofum, divides into coital 5 and as foon as it emerges thence, Js again fubdi- two Branches, or Portions, a. hard and a foft one. The fan/

entring a little Sinus in the upper part of the Bone that conluiutesthe Barrel of the Ear j fends off a Twig which ditttibutes itl'clf into the Dura Mater, except fome fmall Twigs which go to the Membrane that lines the Ear, to the internal Mufcles that line the Ear, and the fine Mem-

vided into three nearly equal Branches. The vfpermojl paffing the Foramen Lacerum into the Orbit of the Eye, is immediately fubdivided into three lefs Branches ; the firft of which, after fending Twigs to the Tunica Ad- nata, Glandula Lacrymalis, the Mufcks that draw up th

Nofe, and the orbicular Mufcles, running over the Mufcle brane that cluthes the infide of the Cavity of the Apo- which draws up the upper Eye-lid, is fpent on the Mufcles fhyfis Mamdians. After this, the hard Branch fends off two

of the Forehead, and the common Integuments of the fore- other Twigs, one to the eighth Pair, the other to the Tyin- part of the Head. fanum, whofe Chord it forms ; whence creeping over the

The fecond Branch running under the Pathetics and Malleolus, it goes out of the Ear, and fends a Ramification Motorii, is divided into two ; whereof tile outer and fmaller fends off feveral FibrtlU into the Fat that envelopes the Opricjferoej and joining wirh others from the third Pair, forms a fort of Plexus on the Trunk of the Optic Nerve j whence FibrtlU are detach 'd into the Mufcuhs Vepr'mens,

to the Tongue.

The fame hard Branch, coming out of the Procejfus Ma- miSaris, lends fome Twigs to the Maffeter, and others to the Glands about the Ear ; where it divides into two other , Ramifications ; the interior bellowed on the Glands, the Adducent, and the Tunica Sclerotica. The inner and bigger Check, and the upper Lips, the reft on the lower Palpe- Slip is fubdivided into four Twigs ; the firft running over bra, and the external part of the Face. The exterior Ra- the Optic Nerve, enters the Sclerotica, and is fpent in that mification, bellowing fome FibrilU on the Glands out of Membrane. The fecond, returning into the Skull by a which it iffues, divides into two; the upper diftributed peculiar Perforation, pierces the Dura Mater, and, fome- into the Quadraius and outer patts of the under Lip ; the times turning back again, paffes out of the Skull thro one lower fpentun the Integuments of the fore and lateral part of the Holes of the Cribriforme, and is diftributed into the of the Neck, lower Jaw, and the Mafloidal Mufcle. interior Membrane of the Nofe. The third Twig is fpent The foft and larger Portion of this Pair divides into partly on the Eye-lids and theit orbicular Mufcles, the ex- three Ramifications, the upper whereof paffes a fmall Fo- ternal Integument of the Nofe, and the Mufcles which rameu into the Concha, where expanding, it forms a fine draw it upwards. The fourth is diftributed by feveral Membrane which lines its inner Surface. 'The fecond and Twigs into the Eye-lids and orbicular Mufcles. The third third Ramifications are alfo fpent on the inner parts of the Slip of the upper Branch is fpent on the Glandula Innomi- " nata and Tunica Adnata.

The lefs inferior Branch, e'er it leave the Skull, enters the Orbit of the Eye, and running along the outfide of the Mufculus Abducens, goes out again at a little Perforation pe- culiar to it; after which ir divides into feveral Fibres, fome of which go to the Integuments of the Cheeks; the reft to the Mufcles that raife the upper Lip. As foon as it quits

Concha and femicircular Duels, which they furnifh with Membranes, the immediate Organs of Hearing. See Hearing.

Eighth Pair of Nerves, or the Par Vagum, fprings from the Medulla Oblongata, a little above the Olivaria Corpora, and paffes out of the Skull thro the fame Perforations with the lateral Sinus's of the Dura Mater.

This, in its progrefs, is join'd by the Par Acccffbmm, and a the Skull at the third Foramen, it is fubdivided into three little further by a Twig of the hard part of the feventh Pair little Branches, the firft of which, after fome Twigs be- andat the fecond Vertebra of the Neck by the I\ferz.»s that iffue ftow'd on the Maffeter, the Teguments of the Face, the from the Cervical Marrow ; and detaches feveral Twins to Gums, and upper Teeth ; enters a peculiar Sinus of the the Mufcles of the Larynx, Gula, Neck, £-?c. particularly Bone making the lower part of the Orbit, and goes out the Gan-Jioform Plexus, form'd by its Union with a Branch at a Hole particular to it; afterwhichit dividesinto feveral of the Intercollal. Hence defending to the Thorax it Fibril* which go to the Teguments of the Face, the, upper makes another Plexus under the Clavicle, whence arifes the Lip, the Mufcle that draws the lower part of the Nofe Recurrent Nerve on the right fide, as on the left it has its laterally, and the inner Mufcle of the Nofe. Rjft. f rom t he Trunk of the Nerve itfelf. The right Re-

rhejccondjmall Branch running downwards behind the currenr is reflected at the Axillary Artery, the left at the Du3s which go from the Nofe to the Fauces, is divided defending Branch of the Aorta ; each running afide the

Tra-