716 
ON TUBERCLES IN DIFFERENT ORGANS. 
numerous tubercles disseminated in the tissue of the lungs. At 
other times the resonance of the thorax is every where normal ; 
the respiration is perfectly natural ; and, guided by these data, 
we conclude that there are no tubercles in the lungs. When, 
however, we inquire more carefully into the case, we find that 
some of the breed have died of phthisis, or they have had 
swellings about the jaws or other parts, or their health has been 
delicate, or their growth has been stinted, and ultimately we 
find that the lungs contain tubercles, although auscultation is 
powerless to demonstrate their presence. Tubercles are mani- 
festly hereditary ; and whenever they exist in one parent, the 
descendents will be more or less under the influence of tubercular 
diathesis, even before this state of the oeconomy has revealed 
itself by any external symptom. 
Tubercles may appear in the lungs at a very early period of 
life, but they are oftenest found in the few years that follow 
puberty. It is also the fact, that although, after the age of 
puberty, the patient may appear to escape from the fatal influence 
of tubercular manifestation, the predisposition still exists, and the 
malady may return sooner or later. 
Sometimes the lungs are suddenly invaded by tubercles, the 
generation of which progresses with frightful rapidity. This form 
of phthisis is promptly fatal. 
Pulmonary tubercles follow precisely the same course as tuber- 
cles in general. According to Andral, they appear at first as small, 
white, friable masses, which sooner or later become soft, and are 
evacuated, leaving behind them an ulcerous cavity, or vomica, 
which generally spreads more and more, but in some instances 
remains stationary, and in a very small proportion of cases fills up 
and cicatrizes. 
It is rare to find only one tubercle in a lung, and it is also rare 
to find them in one lung and not in the other. They have the 
greatest tendency to be developed in the right or larger lobes. 
They are usually in the interior of the lung; in others they are 
quite superficial and situated immediately under the pleura. They 
gradually converge as they increase in size and number, and, 
uniting, form tubercular masses. These assume the form of 
calcareous concretions, or they soften, and are evacuated into the 
bronchi, leaving caverns in the lungs, known by the name of 
vomicse. 
The matter being evacuated, we may be encouraged to hope 
that the parietes of the cavern will heal, and the patient escape 
the danger that threatened him : but these hopes are delusive ; 
a predisposition to the generation of tubercles still remains. They 
will with greater or less rapidity be generated in the pulmonary 
tissue, and he will eventually fall a victim to their presence. 
On examining the lungs of a person or an animal that has 
