246 PRACTICE OF PHYSIC. 



DCCCLVIII. DCCCLIX., it may, with reason, ,be con- 

 cluded, that an abscess, or, as it is called, a vomica, is formed 

 in some part of the pleura, and most frequently in that portion 

 of it investing the lungs. Here purulent matter frequently re- 

 mains for some time, as if enclosed in a cyst : but commonly it 

 is not long before it comes to be either absorbed, and transferred 

 to some other part of the body ; or that it breaks through into 

 the cavity of the lungs, or into that of the thorax. In the latter 

 case, it produces the disease called empyema ; but it is only 

 when the matter is poured into the cavity of the bronchiae, that 

 it properly constitutes the phthisis pulmonalis. In the case of 

 empyema, the chief circumstances of a phthisis are indeed also 

 present ; but I shall here consider that case only, in which the 

 abscess of the lungs gives occasion to a purulent expectoration. 



DCCCLXVIII. An abscess of the lungs, in consequence of 

 pneumonia, is not always followed by a phthisis : for sometimes 

 a hectic fever is not formed ; the matter poured into the bronchiae 

 is a proper and benign pus, which is frequently coughed up very 

 readily, and spit out : and, though this purulent expectoration 

 should continue for some tune, yet, if a hectic does not come on, 

 the ulcer soon heals, and every morbid symptom disappears. 

 This has happened so frequently, that we may conclude, that 

 neither the access of the air, nor the constant motion of the 

 lungs, will prevent an ulcer of these parts from healing, if the 

 matter of it be well-conditioned. An abscess of the lungs, 

 therefore, does not necessarily produce the phthisis pulmonalis ; 

 and if it be followed by such a disease, it must be in conse- 

 quence of particular circumstances, which corrupt the purulent 

 matter produced, render it unsuitable to the healing of the 

 ulcer, and at the same time make it afford an acrimony, which, 

 being absorbed, produces a hectic and its consequences. 



DCCCLXIX. The corruption of the matter of such ab- 

 scesses may be owing to several causes; as, 1. That the matter 

 effused during the inflammation, had not been a pure serum fit 

 to be converted into a laudable pus, but had been united with 

 other matters which prevented that, and gave a considerable 

 acrimony to the whole: Or, 2. That the matter effused, and. 

 converted into pus, either merely by a long stagnation in a 

 vomka, or by its connexion with an empyema, had been so 



