THE CONFESSION OF A REFORMED SMOKER. 81 



bearings of the facts, and the intimate relation of the diverse symp- 

 toms to each other in tobacco-sickness, it is, perhaps, necessary to 

 map out the pneumogastric nerve and indicate its function, which is 

 not fairly deducible from its name. The origin of nearly every pair 

 of cranial nerves has been traced into the vital bulb, the medulla' ob- 

 longata, or continuation and expansion of the spinal cord as it passes 

 into the cranium, to blossom into the complex structure of the brain. 

 This tract enters the cranium in six bodies, united in a bulb, and 

 continuing the six strands of the marrow, namely the two pyramidal 

 continuing the anterior white strands of the spinal stem, the two 

 olivary the interior and partly lateral strands of gray neurine, and 

 the two restiform (corpora restiforma) the posterior white strands. 

 There are two ways of dissecting a brain, each of which has merits 

 of its own for special purposes. The first and more general consists 

 in examining the encephalic mass from above downward, by remov- 

 ing it in successive slices. For descriptive anatomy, and for patho- 

 logical examination, this method is perhaps preferable. The second 

 consists in examining and unraveling the structure from the spinal 

 bulb upward, by tracing its fasciculi as they expand, radiate, and en- 

 large ; and I am inclined to think that this method has its advantages 

 in tracing the genesis of psychical phenomena. To this bulb all the 

 complex activities of the cerebro-spinal axis finally refer themselves : 

 it is properly the calyx from which spring the three ganglionic masses 

 the mesocephale, cerebellum, and cerebrum. The par vagum, gen- 

 erally known as the pneumogastric nerves, spring laterally from this 

 bulb, and properly include three pairs of nerves, namely the glosso- 

 pharyngeal, which supply the base of the tongue with sensation, and 

 connect and coordinate the motions of the organ with those of the 

 pharynx and of the digestive function; the pneumogastric, which, 

 with the preceding, have their origin in filaments springing from the 

 groove between the olivary and restiform bodies ; lastly, the spinal 

 accessory, originating laterally from the medulla spinalis, but joining 

 the main stem near its ganglion, and distributed to the lateral muscles 

 of the neck. From the cervical tract of this nerve, which is triple in 

 its origin, spring filaments or strands, that join the sympathetic and 

 lingual nerves, others that proceed directly to the pharynx, and still 

 others known as its cardiac ramifications. The superior laryngeal 

 nerve, distributed to the upper portion of the larynx, and the recur- 

 rent nerve, distributed to the muscles of the larynx, are both portions 

 of the pneumogastric system. This pair of nerves passes through the 

 jugular foramen just anterior to the vein of the same name, and sep- 

 arates into three parts. In the foramen it presents a ganglionic ex- 

 pansion, and below it a long gangliform swelling which communicates 

 with the facial, spinal accessory, sympathetic, glossopharyngeal, and 

 superior spinal nerves all of which are here gathered into a kind of 

 elongated plexiform bundle. At this point the nerve has the compact- 



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