50 



an especial manner, contain the principle of vegetable life, essential to 

 the existence of every organized body possessing the power of diges- 

 tion, absorption, circulation, secretion, and nutrition ? Finally, is it 

 not probable, that in man, the system of the great sympathetic nerves, 

 has a great share in occasioning a number of diseases, and that the im- 

 pressions with which patients are affected, arc referred to their nu- 

 merous ganglions, while the brain is exclusively the seat of intellect and 

 thought* ? 



These suggestions will, doubtless, be answered in the affirmative, if 

 one considers the origin, the distribution, and the peculiar structure of 

 these nerves, the acute sensibility of their branches, as well as the disor- 

 ders attending their injury. 



Extended along the vertebral column, from the base of the skull to the 

 lower part of the sacrum, these great nerves, in some measure parasitic, 

 do not arise from the branches supplied them by the fifth and sixth pairs 

 arising from each side of the brain; they live and are nourished, as it 

 were, at the expense of all the nerves of the spinal marrow, from which 

 they receive branches, so that there is not one of them, from which one 

 can say, that the~*great sympathetics arise exclusively. The numerous 

 ganglions which are distributed along their course, divide them into so 

 many small systems, from which arise the nerves of the organs nearest to 

 them. Amidst these bulgings, considered by several physiologists, as so 

 many little brains, in which is performed the elaboration of the fluid 

 which they transmit to the nerves, no one is of more importance than the 

 semi-lunar ganglion, situate behind the organs which occupy the epigas- 

 tric region, and from which those nerves originate, which are distribu- 

 ted to the greater part of the viscera of the abdomen It is to the 

 region occupied by that ganglion, in which the great, sympathetic nerves 

 unite, and which may be considered as the centre of the system formed 

 by their union, that we refer all our agreeable sensations; there it is 

 that we feel in sadness, a constriction which is commonly referred to 

 the heart. Thence, in the sad emotions of the soul, seem to originate 

 those painful irradiations which trouble and disorder the exercise of all 

 the functions f. 



The numerous filaments of the great sympathetic nerves are finer, they 

 are not of the same whitish colour, nor of the same consistence as the 

 filaments of the cerebral nerves. On that account, they are less easily 

 dissected^, the nervous fibrillae are less distinct, their reddish chords are 



* These opinions on the uses of the great sympathetic nerves, are explained in my 

 Essay on the connexion of life with the circulation. This essay was published before 

 any thing 1 that has appeared on the same subject. Consult the .*' Memoires de la So- 

 cie"te Medicale pour 1'an VII." Jl-uthor's Note. 



f Consult on the subject of the epigastric centre, Van Helmont, who calls it the 

 archeus ; Buftbn, Bordeu, Barthez, and Lacaze, who give it the name of the phrenic 

 centre, because they ascribe to the diaphragm what belongs to the nervous ganglions 

 placed in front of its crura. Author's Note. 



t One of the best modes of dissecting them is to macerate the part, in which we wish 

 to trace their ramifications, during two or three days in water ; then place it for a short 

 time in a very dilute acid, or warm spirits, or in oil of turpentine. The filaments of 

 these nerves may be then traced more distinctly. Other processes, which are more 

 complex, are requisite to the dissection of the minuter ramifications, especially those 

 which supply the blood-vessels. Copland. 



Anatomists are perfectly well aware, that none of these processes are to be relied 



