A description of the distribution of the nerves of the human body; with elementary physiological and surgical observations: including Mr. Brookes's nomenclature of the nervous system ... / by G.D. Dermott.

  • Dermott, G. D. (George Darby), 1802-1847.
Date:
1830
Catalogue details

Licence: Public Domain Mark

Credit: A description of the distribution of the nerves of the human body; with elementary physiological and surgical observations: including Mr. Brookes's nomenclature of the nervous system ... / by G.D. Dermott. Source: Wellcome Collection.

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    These are Nerves commencing with single origins from the foremost part of the Me¬ dulla Oblongata, so as to emerge from the depression existing between the Medulla Oblongata and the Pons Varolii. They course directly forwards under the sides of the Pons Varolii, so as to perforate the Dura Mater closely by the side of the Posterior Ephippial Processes, and imme¬ diately below the very termination of the Anterior Edge of the Tentorium against the corresponding Ephippial Process. Each then courses forwards through the centre of the Cavernous Sinus of the correspond¬ ing side, in close cellular cohesion to the outer side of the Internal Carotid Artery, so as to be immersed along with the Artery, amidst the Plexus of minute Veins which constitute the spongy or cellular- like structure of the Cavernous Sinus. It then courses forwards through the Foramen Lacerum Orbitale Superius into the Orbit, and then plunges into the Abductor Oculi Muscle, giving to it Volition. One great peculiarity of this nerve is that when it is in the Cavernous Sinus, mi¬ nute filaments are reflected back from it, which descend upon the surface of the In¬ ternal Carotid Artery through the Canalis Caroticus along witli the Inferior Division of the Vidian Twig of the Par Trigemi- nura, and become united in one with that nerve in the substance of the First Cervi¬ cal Ganglion of the Sympatheticus Maxi¬ mus.* The Vidian Twig and these fila¬ ments thus unite the Nervus Trigeminus and the Nervus Abducens with the Sym¬ patheticus Maximus, i. e. unite the com¬ mon sensibility and voluntary motion of the soft parts of the Face, in a constitu¬ tional manner, with the system of parts supplied by the Sympatheticus Maximus. These filaments correspond exactly with the connecting filaments that extend be¬ tween all the other Ganglia of the Sympa¬ theticus Maximus and the Spinal Nerves, as they are emerging from the Foramina Intervertebralia, and which establish a con¬ stitutional connection or sympathy between the Vital Organs that derive their peculiar sensibility and faculty of involuntary mo¬ tion from the Sympatheticus Maximus, * These filaments are probably received by the Nervus Abducens and Par Trigeminum from the Sympathetic; there are also slender connections of the Sympathetic with the Oph¬ thalmic Branch of the Fifth Pair, and with the Motor Oculi or Third Pair, by which the Len¬ ticular-Ganglion is conjoined with the Sym¬ pathetic.—These filaments between the Sym¬ pathetic and the Cerebral Nerves establish a sympathy between the various parts of the Head and the Viscera of the Body. and the voluntary muscles and parts pos¬ sessed of common sensibility, that consti¬ tute the limbs and the various other parts of the system which are supplied by the Spinal Nerves—the Nervus Trigeminus being the Spinal Nerve of the Face. Seventh pair—Is generally described as consisting of the Nervus Acousticus, Portio Mollis, or the Auditory Nerve; and the Portio Dura, or Nervus Com- municans Faciei. The Nervus Acou¬ sticus or Portio Mollis, is the nerve which conveys and bestows the sensibility of Hearing to the Internal Ear, or Laby¬ rinth. This nerve is usually said to com¬ mence upon the upper surface of the Me¬ dulla Oblongata, or the floor of the Fourth Ventricle, by transverse medullary lines, (called strise transversse) which pass out¬ wards from the Crena of the Medulla Oblongata across the upper surface of the Medulla Oblongata, these and the Crena constituting those marks on the floor of the Fourth Ventricle denominated Calamus Scriptorius. These striae become collect¬ ed, and pass off in the form of a single nerve, or the Portio Mollis, from the fore and lateral part of the Medulla Oblongata. It is then continued obliquely backwards and outwards, being peculiarly soft in its substance, and lodging in a superficial sulcus on its fore side the Portio Dura. The two are then continued into the Fo¬ ramen Auditivum Internum. On sepa¬ rating the Portio Dura from the Portio Mollis, we find the filament situated be¬ tween them, denominated the Portio In- terpositum Durum et Mo Hem, or Portio Media. This arises contiguous to the commencement of the Portio Mollis, and passing forwards for a short distance be¬ twixt the two nerves, joins the Portio Dura, as the two nerves are about to en¬ ter the Foramen Auditivum Internum. The Nervus Acousticus, reaching the bot¬ tom of the Foramen Auditivum Internum, abruptly splits into its component fila¬ ments, which pass through all the Fora- minulse in the Fossula Parva, (a small depression constituting the upper part of the Bottom of the Foramen Auditivum Internum) with the exception of the largest and foremost of these small Foraminulae, which is the commencement of the Aque- ductus Falopii, and gives progress to the Portio Dura; and also all the Foramin- nulse in the Fossula Magna (which con¬ stitutes the inferior and major portion of the bottom of the Foramen Auditivum Internum) : the filaments which enter the Labyrinth by piercing the Fossula Parva, correspond to, and are dispersed upon, the Osseous Cavity of the Vestibulum