'245 
PATHO 
monia (or inflammation of the lungs), can only lead to a 
probable fufpicion of an afreCtion of the heart; iince they 
are by no means conftant attendants on carditis ; and the 
former very frequently attends other cafes of pneumonia. 
(Wjlfon on Febrile Difeafes, vol, iv.) Upon the fame 
grounds Dr. Cullen accords with the observations of 
Vogel, that “ the fymptoms of carditis are nearly the fame 
with thofe of peripneumony, but in general more fevere.” 
In this perplexity as to the melt: important of cardiac 
difeafes, it mull be highly gratifying to have an addition 
to our ufual modes of diagnofis. This has been at¬ 
tempted, as our readers are probably aware, by Laennec. 
This author perceived that many of the movements of 
the thoracic vifeera were audible , and conceived the de- 
fign of rendering this circumftance ufeful to his profef- 
flon. Finding the application of the ear to the cheft inef¬ 
ficient to give very accurate information on the fubjeCt, 
and a&ing on the eftablifned knowledge of the increafe 
of found when palling through tubes, the author invented 
an inftrument which he called, from its life, a ftethofeope. 
It is merely a cylindrical piece of denfe wood, about one 
foot in length and four inches in circumference, having 
a hole drilled longitudinally through it of about three 
lines in diameter. The lower end of the inftrument is 
placed on the thorax of the patient, the upper to the ear 
of the phylician ; and through this perforation the ruffl¬ 
ing of the air into the air-cells in infpiration, See. is heard. 
We pafs over this however for the fame reafon that we did 
when fpeaking of pulmonary complaints, becaufe we 
cannot ourfelves difeover the phenomena Laennec de- 
feribes, though we are willing to admit this may be the 
refuit of want of tad. As far as regards the motions of 
the heart, the ftetholcope feems entitled to more credit; 
and by its life, and by means of the important difeufiion 
now going on, we may hope foon to fix the diagnofis of 
difeales of the heart on the firmed grounds. 
. Before entering on Carditis, it will be neceflary to 
fpeak of the motions which are heard through the me¬ 
dium of this cylinder during health. We fpeak firft of 
the extent at which the beating of the heart is heard. 
The beating of the heart is heard mod diftindly when 
the cylinder is applied to the left fide, between the fifth 
and feventh ribs, or to the lower part of the fternum, the 
aClion of the left fide of the heart being bell heard in 
the firft: lituation, the adion of the right in the fecond. 
It is alfo heard in a lefs degree ever the right fide. It is 
more diftinCt during exertion, &c. and in thin people, 
the beating being lefs perceptible and lefs diffufed in fat 
perfons. In the former, indeed, we fometimes hear the 
beating of the heart all over the fternum, on the left fide 
as far as the clavicle, and fometimes in the fame lituation 
on the right fide. When the beating of the heart is 
heard beyond thefe limits, or even within them, if the 
patient has flight dyfpnoea, is unable to take much ex- 
ercife on account of fliortnefs of breath, palpitation fu- 
pervening to flight emotions, See. we may fufpeCt difeafe 
of the heart, though thefe fymptoms may continue for 
years without any further changes. It feems that, when 
the parietes of the heart are thin, and confequently weak, 
the beating of the heart is heard over the greater part of 
the thorax ; and that the reverie happens when thofe 
parts are thickened. It fliould be remarked, however, 
that the increafe in the general fize of the heart eaufes 
its beating to be externally heard. 
The next point to be attended to in the ufe of the 
ftethofeope, is the degree of impulfe which the beating of 
the heart gives to the cheft. Laennec calls this the 
Jhock. It nuift not however be confounded with the 
movements of refpiration, which, when Ihort and fre¬ 
quent, as in fevers, &c. may be miltaken for it. It feems 
that this (hock is audible through the cylinder when it 
cannot be felt by the hand. It is rather indiftinCl in 
healthy and fat perfons; and is generally in a direct ra¬ 
tio to the thicknefs of the walls of the ventricle, conl'e- 
L O G Y. 
quently in an inverfe ratio to the extent of the beating 
of the heart. It is only heard during the contradion of 
the ventricles ; or at lead the contraction of the auricles, 
when audible, produces a more diftant and indiftinCl 
found. The Jhock is fcarcely heard at all when the 
parietes of the ventricles are morbidly thin. The in- 
creafed force of this thock is viewed, therefore, as pre- 
fumptive evidence of thickening of the parietes of the 
ventricles, while its abfence feems to indicate dilatation, 
of the ventricles. Laennec endeavours to point out the 
phenomena developed by the ftethofeope when both 
the latter dates of difeafe are prefent; but thefe are by 
no means fatisfaCtory. The Jhock is heard over the fifth, 
and feventh ribs on the left fide, over the lower half of 
the fternum, or, when that bone is fhort, over the epi- 
gaftrium. Coinciding with the (hock above-mentioned, 
and coinciding alfo with the pulfe, we hear, by means of 
the cylinder, an obtufe found which lafts about two fe- 
conds : this is produced by the contraction of the ven¬ 
tricles. Immediately afterwards we hear the contraction 
of the auricles announced by a Ihort acute noils, which 
Laennec has compared to the found produced by the 
lapping of a dog or from the valve of a bellows. He de¬ 
nominates it claquement, a word well tranflated by. our 
Englifh clacking. This clacking, the fign of the con¬ 
traction of the auricles, is followed by the perfeCt in¬ 
action of the heart for a fhort fpace of time. Then the 
obtufe noife, and riling oryAoc/c of the ventricles, is again 
heard ; which is inftantly followed by the clacking ; and 
fo on. The proportion of thefe motions is nearly as 
follows: of the time occupied by all the motions of the 
heart, one fourth is taken up.by the clacking, or con¬ 
traction of the auricles ; one fourth by abfolute reft ; and 
one half by the contraction of the ventricles. Having 
thus explained, in a certain degree, the application of this 
new inftrument, we return to Carditis. 
As between inflammation of the brain and arachnoid 
membrane, as between that of the pleura and of the 
lungs, the fymptoms vary, fo alfo do we find them vary¬ 
ing as the nnifcular fubftance of the heart, or its inveft- 
ment, the pericardium, is the feat of this adion. This 
opinion is of courfe to be received with fome dillruft, be¬ 
caufe our knowledge of the difeafes of the heart is very- 
limited. We reft it chiefly on the authority of Laennec, 
than whom no one has performed more important fer- 
vice in elucidating the nature of the difeafe we are 
treating of. 
The principal divifions of difeafes of the heart are 
made with reference to the morbid products or altera¬ 
tions of ftruCture found on difiedion. Though we pro- 
pofe to mention curforily the chief of thefe, it is by no 
means our intention to treat of them fully. We fliall 
rather confine ourfelves to a minute and laboured de¬ 
tail of the forms and diagnoftics of inflammation as it 
alfeCts the various parts or ftruCtures of the prime mover 
of animal life. We do this, becaufe it feems to us, that 
morbid anatomy is of no life unlefs it leads to a difeo- 
very of the mode of aCtion by which difeafed ftruCtures 
are built lip ; for that, in the majority of cafes, when 
once formed, all endeavours to remove them by medical 
ikill are unavailing, is a truth but too well known. 
Inflammation of the inverting membrane of the heart, 
or pericarditis, has been ufually held to be uncliftinguifti- 
able from inflammation of the heart itfelf; and, when 
acute, this mull necelfarily be true of all but the firft 
periods of the difeafe, becaufe its connection with its 
inclofed vefiels will of courfe bring on aCtual Carditis. 
The fymptoms of acute pericarditis are Ample accelera¬ 
tion of the movements of the heart; viz. quick and hard 
pulfe, rednefs of the capillary fyftem as tnanifefted in the 
ikin, added to the ufual fymptoms of phlogofis of ferous 
membranes. The acceleration alluded to is evidently- an 
efFeCt of irritation of the mufcular fibres of the heart ; 
and, this being uniformly exerted over the whole of the 
heart, 
