PNEUMONIA. 71 



error has been to mistake tubercular vomicae, or interlobular pleuritic 

 effusions, for abscess of the lung. 



When abscess, however, docs form in an hepatized lung, the 

 passage of air through the liquid will be indicated by the gurgling or 

 cavernous rhonchus ; and when the cavity has been emptied of the 

 pus by expectoration, pectoriloquy and the cavernous respiration will 

 be added to this sign. 



Pneumonia may also terminate in gangrene ; but this is nearly 

 as rare a termination as abscess. The distinctive physical sign of 

 gangrene is the foetid odour emitted from the diseased part in respi- 

 ration and cough ; and the expectorated matter is also extremely 

 foetid. This change is usually attended by a collapse of the features, 

 and great prostration of the vital powers. 



Morbid appearances. — In the first stage of pneumonia, the sub- 

 stance of the lung presents an increase of weight and density ; it is 

 infiltrated with a frothy, sanguineous serosity, in considerable quan- 

 tity ; it pits on pressure, but yet is still somewhat crepitant ; its 

 integral cohesion is diminished, for it can be easily broken down 

 between the fingers ; the mucous membrane of the small bronchi is 

 of a deep red colour. 



In the second stage, or that of hepatization, the lung no longer 

 crepitates ; it now sinks in water ; and, when cut into, a red liquid, 

 not frothy, nor so abundant as in the preceding stage, flows from it. 

 Externally, the lung is of a deep red colour, and internally it is 

 studded with a number of red granulations, with patches of a white 

 colour, marking the vessels, interlobular septa, &c., less affected 

 with the inflammation. Its friability is very great ; in many cases, 

 it is sufficient to press it between the fingers to crumble and reduce 

 it to a reddish pulp. The term " hepatization" is not strictly appli- 

 cable to this condition of the lung ; that of red softeyiing gives a 

 much more accurate idea of the real condition of the inflamed organ. 



In the third stage, the pulmonary tissue, dense, compact, and im- 

 pervious to the air, as in the preceding stages, presents a charac- 

 teristic grayish colour. When examined with a lens, it presents 

 granulations of a white or gray colour ; these can also be seen by 

 the naked eye in many instances. In a more advanced degree, the 

 colour is of a straw, or sulphur yellow, owing to the greater quantity 

 of liquid pus ; the texture is considerably destroyed ; and if the lung 

 be cut, and the tissue slightly compressed, without crumbling it, 

 small drops of pus appear on the surface; these seem to issue either 

 from the orifice of the capillary bronchi, or from the granulations 

 themselves. This condition of the lung may be defined as " gray 

 softening P 



Treatment. — Pneumonia is one of those diseases whose treatment 

 is at once simple and efficacious, provided it be adopted at an early 



