ANA’ 
.ftomach. From the dillributipn of this par vagum, we 
may learn, how tickling the fauces with a feather or any 
fuch fubftance, excites a naulea and inclination'to vomit; 
why coughing occalions vomiting, or vomiting raifes a 
cough, Hence we lee how the nervous afthma, thetuffis 
eonvulliva, and chin-cough, are attended with a ftraiten- 
i:ng of the glottis; why food difficult to digeft occalions 
the aftlnna to weakly people; and why emetics have fre¬ 
quently cured the afthma very fpeedilv; why an attempt 
to vomit is fometimes in danger of fuffbeating a ft lunatic 
people; why the luperiororifice of the ftomach is fo fen- 
lible as to be looked on as the feat of the foul by fome 
anatomifts;. why people fubject to diftenftons of the fto¬ 
mach have fo often the fenfation of balls in their bread: 
and throatwhy the globus hyftericus is fo often attended 
with a violent ftrangulation.at the glottis. 
The ninth pair of nerves comes from the inferior part 
of. the corpora pyramidalia, to go out of the fkull at their 
proper holes of the occipital bone. After their egrefs 
they adhere for fome way firmly to the eighth and inter- 
codal; and then fending a branch, that in many fubjefts 
rs joined with branches of the fird and fecond cervical 
nerves, to be didributed to the thyroid gland, and muf- 
cles on the fore-part of the trachea arteria, the ninth is 
loft in the mufcles and fubdance of the tongue. Some 
authors have thought this nerve, and others-have efteem- 
ed the third branch of the fifth pair of nerves, to be the 
proper gudatory nerve. 
The tenth pair rifes in feparate threads from the fidesof 
the fpinal marrow, to go out betw een the os occipitis and 
fird vertebra of the neck. After each of them has given 
branches to the great ganglion of the intercodal, eighth, 
ninth, and fird, cervical nerves, it is didributed to the 
ftraight oblique, and fome of the extenfor, mufcles of the 
head. As the intercodal is about to enter the thorax, it 
forms another ganglion, from which nerves are fent to 
the trachea and to the heart; thofe defigned for the heart 
joining with the branches of the eighth, and moft of them 
pafling between the two great arteries and the auricles to 
the fubdance of that mufcle. The intercodal after this 
Confuting of two branches, one going behind, and the 
other running over the fore-part of the lubclavian artery, 
forms a new ganglion, where the two branches unite be¬ 
low that artery; and, then defeending along the lides of 
the vertebra; of the thorax, receives branches from each 
of the dorfal nerves; which branches appearing to come 
out between the ribs, have given the name of intercojlal 
to the whole nerve. The almod univerfal connection and 
communication which this nerve has with the other nerves 
of the body, may lead us to underdand the following and 
a great many more phenomena : Why tickling the nofe 
caufes fneezing; why the too great quantity of bile in the 
cholera occalions vomiting as well as purging; why peo¬ 
ple vomit in cholics, in inflammations or other irritations 
of the liver, or of the duffs going from it and the gall¬ 
bladder; why a done in the kidneys, of ureters, or any 
other caufe irritating thofe organs, fhould fo much more 
frequently bring on vomiting and other dif'orders of the 
ftomach, than the ftone or any other ftimulating caufe in 
the bladder does ; why vomiting is a fymptom of danger 
after child-birth, lithotomy, and other operations on the 
parts in the pelvis; why the obftruftions of the menfes 
are capable of occadoning ftrangulations, belching, cho¬ 
lics, ftomach aches, and even convullions in the extremi¬ 
ties ; why veficatories, applied from the ears to the cla¬ 
vicles of children labouring under the tuflis eonvulliva, 
are freqtiently of great fervice; why worms in the ftomach 
or inteftines excite an itching in the nofe, or grinding of 
the teeth; why irritations in the bowels or the belly occa¬ 
fion fometimes univerfal convuldons of the body. 
The Spinal Nerves rife generally by a number of 
feparated fibres from both the fore and back part of the 
medulla fpinalis; and loon after form a little knot, or 
ganglion, where they acquire ftrong coats, and are ex¬ 
tended into firm cords; but the ganglion is entirely form- 
T O M Y. % 
ed by the pofterior bundle. They are diftinguilhed by 
numbers, according to the vertebras irqm between which 
they come out; the fuperiof of the two bones forming 
the hole through which they pafs, being the one from 
which the number is applied to each nerve. There are 
generally faid to be thirty pair of them: leven cervical, 
which come out between the vertebra; of the neck ; twelve 
dorfal , between the vertebra; of the back; five lumbar, 
between the vertebrae of the loins; and fix pair from the 
falfe vertebrae. 
Thejirjl cervical pair, of the nerves fends its largeft 
branches backwards to the extenfor mufcles of the head 
and neck ; and many fibres advance fo far as to be con- 
r.efted with the portio dura.of the auditory nerve. Hence 
polfibly it is, that a clavus hyftericus changes fuddenly 
fometimes from the forehead to a violent pain and fpafm 
in the back-part of the head and neck. The fecond cer¬ 
vical has a large branch that comes out at the exterior 
edge of the ftemo-maftoideus mufcle, and it is afterwards 
diftributed to the integuments of the fide of the neck and. 
head, parotid gland, and external ear, being connected to 
the portio dura of the auditory nerve, and to the firft cer¬ 
vical. The remainder is fpent on the levator fcapulae 
and the extenfors of the neck and head. The irritation- 
of the branches of this nerve in an inflammation of the 
parotid gland, is probably the caufe why the neck is pain-, 
ed fo far down as the clavicle, the head is drawn towards 
the fhoulder of the affefted fide, and the chin is turned to 
the other fide. The third pair of the neck pafles out be¬ 
tween the third and fourth cervical vertebrae; having im¬ 
mediately a communication with the fecond, and fending 
down a branch,, which, being joined by a branch from the 
fourth cervical, forms the phrenic nerve. This nerve en¬ 
ters the thorax between the fubclavian vein and artery j 
and then, being received into a groove formed for it ia 
the pericardium, it has its courfe along this capfula of the 
heart, till it is loft in the middle part of the diaphragrii. 
The other branches are diftributed to the mufcles and in¬ 
teguments at the lower part of the neck and top of the 
flioulder. No wonder then that an inflammation of the 
liver or fpleen, an abfeefs in the lungs adhering to the 
diaphragm, or any other caufe capable of irritating the 
diaphragm, fhould be attended with a fliarp pain on the 
top of the flioulder, as well as wounds,, ulcers, See. of 
this mufcle itfelf. If the irritation of this mufcle is very 
violent, it may occafion that convulfive contraction of the 
diaphragm which is called an hiccough ; and therefore art 
hiccough in an inflammation of the liver has been juftly 
declared to be an ill fymptom. An irritation of the tho¬ 
racic nerves which produces fneezing may fometimes free 
the phrenic nerves from any fpafm they occafion : fo that 
fneezing fometimes takes away the hiccough; and a de¬ 
rivation of the fluid of the nerves any other way may do 
the fame thing; or the hiccough may alfo be fometimes 
cured by drawing up into the noi'e the finoke of burning 
paper or other acrid fumes, fwallowing pungent or aro¬ 
matic medicines, and by a furprife, or any other ftrong 
application of the mind.in thinking, or in diftinguifhing 
objects: or, when all thefe have failed, it has been put 
away by the brifk ftimulus of a bliftering plafter applied 
to the back. The fourth cervical nerve, after fending off 
that branch which joins with the third to form the phre¬ 
nic, and beftowing twigs on the mufcles and glands of 
the neck, runs to the arm-pit, where it meets with the 
fifth, lixth, and feventh, cervicals, and firft dorfal, that 
efcape in the interlaces of the mufeuli fealeni, to come at 
the arm-pit, when they join, feparate, and re-join, in a 
way fcarcely to be rightly expreffed in words; and, after 
giving feveral confiderabie nerves to the mufcles and in¬ 
teguments which cover the thorax, they divide into feye- 
ral branches, and are diftributed to all the parts of the 
fuperior extremity. The tituation of thefe branches in 
the axilla may let us lee how a weaknefs and atrophy 
may.be brought on the arms by long-continued prelfure 
of crutches, or fuch other hard fubftances, on this part; 
