92 
PATHOLOGY. 
laws may beinfcrutable, painful fenfations and difordered 
fan&ions are. but too apparent. The great difficulty, 
therefore, which attends the ftudy of fymptomatology, 
is not to perceive fymptoms, but their congeries or catena¬ 
tions j and to obferve what are really the primary fymp¬ 
toms, and what are fympathelic, or fecondary: for it is 
on thefe obfervations that the diftinguiffiing of one dif- 
eafe from another depends. It was in this branch of 
pathology, in the (liagnojis, that Hippocrates and Syden¬ 
ham arrived at lo great a degree of perfection. Indeed, 
i-n the writings of the former phylician, we find fo excel¬ 
lent a fyftem of diagnofis, that we may even now turn 
to the ftudy of it with great advantage. We have enu¬ 
merated fome of the leading rules of Hippocrates’s 
fymptomatology; rules which enabled him to difcrimi- 
nate difeafes with great exaftnefs, ignorant as he was of 
the knowledge of phyfiology, ignorant even of all that 
regarded the pulfe except its molt violent actions. Of 
late, a return to thefe rules has been inculcated by one of 
the firll practical phyficians of the age we live in, Dr. 
Marlhall Hall : he has ffiown, that, though we had fo far 
deviated from the rules of Hippocrates as no longer to 
mention them, yet that all fcientific phyficians had made 
theminuteft obfervations on the phenomena of difeafe in 
their own minds, and had even fixed the identity of many 
complaints from the conviction thefe minute circum- 
ftances produced, without-however attempting to ana¬ 
lyze the appearances on which this conviction refted. To 
fupply this analyfis has been the objeCt of Dr. Hall ; and 
it mult be confeffed he has done it in the completed 
manner. To explain his meaning more clearly, w r e ffiall 
quote a few lines from him. He obferves that there is in 
practical medicine a circumftance of the firft importance, 
the recognition of a difeafe. The general appearance of 
a patient, the peculiar modification, the particular com¬ 
bination, and mutual influence, of the fymptoms, give a 
general character to-the wliole difeafe, which is recog¬ 
nized and felt by the phyfician of experience and obfer- 
vation. “ Every praCtitioner of medicine is continually 
engaged in the bufinefs of diagnofis as the very ground¬ 
work of his profeffional duties ; and I fear the founded 
and mod enlightened are in the daily habit of aCting 
upon views that they would be at a lofs to defcribe, and 
have not time to analyze.” This paffage is quoted from 
the letter of a phyfician at once learned and experienced. 
It alludes diftinCtly to that general fource of diagnofis 
conftituted by the combination of all the circumdances 
of a difeafe. Dr. Hall adds, that he has had repeated 
opportunity of oblerving an eminent phyfician, on ap¬ 
proaching a patient, and that even during deep, exprefs 
his fentiment refpeCting the nature of the affection and 
condition of the patient; the juftice of which time and 
the event have verified. This circumftance firft con¬ 
vinced him that there was fomething in the general af- 
peCt and appearance of difeafes, on which the experi¬ 
enced phyfician founds a diagnofis, and which it wmuld 
be of the greateft utility to analyze and defcribe. 
Diagnofis, or the ftudy of fymptoms, is founded on the 
obfervance of various phenomena ; the external appear¬ 
ance, the fenfa'tions, and the impaired funllions, of the pa¬ 
tient; not to fpeak of the more remote circumftances, 
which ftiould never be forgotten as the probable caufe of 
the difeafe ; the liability to certain difeafes from age, fex, 
temperament, &c. the effeft of medicines, &c. With 
regard, then, to the appearances of the patient, the firft 
and moll: obvious is the countenance ; the countenance 
is principally compofed and derives its expreffion from 
the aftion of the mulcles ; as the mufcles are capable of 
rapid contractions, are numeroufly fupplied with nerves, 
are the agents wdiich particularly manifeft the ftate of 
the mind, it is evidently a part in which morbid changes, 
either in the circulatory, mufcular, or nervous, fyftem, 
will become apparent: hence it indicates many impor¬ 
tant circumftances to the eye of the praCtitioner. Dr. 
Hall obferves that the following particulars are to be 
noticed with regard to the face. i. The colour, general 
or partial, z. Tumidity or ffirinking; general or par¬ 
tial. 3. Fulnefs or emaciation. 4.. ACtion or inaCtion 
of the mufcles; general or partial, continued or oc- 
cafional, irregular or fpafmodic. 5. The circulation. 
6. Drynefs or moilture; general or partial. 7. The 
temperature. 8. Particular features. 9. General ex¬ 
preffion. 
The acute author juftly direCts our attention, how¬ 
ever, to the previous ftudy of the natural ftate of the 
countenance under various circumftances. He has di¬ 
rected us to confider the delicate and tumid ftate of 
complexion in the infant, the fmallnefs of its features, 
the abundance of cellular tiffue, the fmall development 
of the facial mufcles, their unmarked degree of expreffion, 
the larger and fuller llze of the eyes, the fmallnefs of 
the features generally. In youth, he ffiows that their 
ftates become gradually changed, and approach more 
nearly to the appearance of the adult countenance. He 
fays, however, that it is the nature and force of the cir¬ 
culation, and the condition of the cellular membrane, 
which impart the character to the countenance of 
youth. The circulation is ftrong and arterial ; the cel¬ 
lular membrane injeCted, firm, and elaftic. It is at 
this period and under thefe circumftances, that the ti¬ 
midity and ffirinking, obferved in the different forms 
and ftages of fever, and the changes from fulnefs to ema¬ 
ciation, in certain organic difeafes, are moft remarkable. 
The adult countenance is remarked to have a greater 
development of the mufcular fyftem, and the various 
expreffions of pain, anxiety, &c. are extremely well de¬ 
fined. The diforder of the circulatory fyftem, as indica¬ 
ted by rednefs, lividitv, or pallor, is likewife well defined. 
In old age, on the contrary, the leannefs, the flaccidity 
of the face, the want of colour, &c. are to be noticed. 
Sex further influences the countenance. In the female, 
the mufcular fyftem is lefs developed, the cellular more 
fo. In the ftates of conception, of the firft month of 
pregnancy, during the flow of the catamenia, a peculiar 
tumidity and enlargement of the features is obfervable. 
In advanced pregnancy, on the other hand, we often fee 
thinnefs, anxiety, and uneafinefs, vifible in different de¬ 
grees in the female vifage. 
The temperament falls next under confideration, as its 
principal charafteriftics are -manifefted in the face. 
Mental emotion, too, ffiould not be forgotten. Its in¬ 
fluence is fometimes exerted on the mufcular fyf¬ 
tem, fometimes on the circulation, and fometimes on 
particular features. Serioufnefs, gaiety, morofenefs, 
are characterized by their particular effeCts on the 
countenance, produced principally by means of the 
mufcular fyftem. Continued and deep thought caufes 
this fyftem to be afteiSted with an unufual degree of con- 
tradtion. Expectation and furprife induce a relaxation 
of the mufcles. Anger, fliame, fear, affeCt the circula¬ 
tion principally ; the firft moves the blood upwards, and 
fuffufes the forehead ; (haine dift'ufes a bluffi over the 
cheeks; fear renders the countenance pale and flirunk, 
and induces drynefs of the tongue. Joy and grief equal¬ 
ly occafion a flow of tears. Enthuiiafm animates the 
countenance as it does the bread ; defpondency depreffes 
the expreffion, as it makes the heart beat more feebly. 
External caufes often influence the countenance in a 
manner that it is neceflary to be apprifed of, in order to 
prevent an erroneous diagnofis. The immediate effeCt of 
bodily exertion and of external heat is to fuft'ufe the 
countenance; expofure to cold contrafts the features, and 
frequently induces an appearance of lividity. Repletion 
of the ftomach occafions an appearance of heavinefs and 
of propenfity to fleep, with a degree of ftift'ufion over 
the face. Want induces an oppofite eft’edt, an appear- 
ence of mental and bodily depreffion. Wine fuffufes 
the eyes and face, and, according to its quantity, en¬ 
livens or obliterates the expreffion. 
The next part which falls under our contemplation in 
diagnofis 
