SUB-ACUTE PNEUMONIA. - 111 



appetite has in some measure returned : still the patient 

 mopes about his box, and is frequently found standing 

 with his head in one corner of it, instead of being towards 

 his manger : moreover, neither his blisters nor rowels act 

 kindly; and there is that expression of countenance and 

 general aspect of him altogether, which impresses us with 

 the firm belief that his disease is far from being removed, 

 and that, without — and unfortunately but too often with — 

 very narrow watching on our part, even now we shall lose 

 him. 



Pathology. — The subdued or sub-acute inflammation 

 now besetting the lungs is, we learn from experience, of 

 that kind which tends to alter structure, and lay the 

 foundation for morbid growths such as are never afterwards 

 removed. Now and then pulmonary consumption dates its 

 offset from this stage of pneumonia. More frequently, the 

 alterations in structure are limited to a more firm and 

 complete hepatization, to obliteration of air-cells and bron- 

 chial tubes, and to a conversion of the red hepatization into 

 what is called the grey and ivhite indurations, of which 

 Delafond has presented us with the following description : — 



The grey induration seems oftener to succeed to the 

 red induration or hepatization than to be simultaneously 

 present with it. The parts so affected assume a yellowish 

 or greyish tint; they have acquired weight and consistence; 

 their granules are smaller and closer together; their paren- 

 chyma is easily lacerated ; sometimes compression converts 

 it into a sort of jelly, from which may be drawn out 

 cellular filaments, thickened and indurated : incisions 

 through these masses often discover either a black blood, 

 or a semi-fluid, inodorous, greyish or reddish matter. 



The white induration is the result of still more ad- 

 vanced disease. In this, granules are no longer perceptible; 

 the indurated parts are exceeding dense, and altogether 

 impermeable to air; when compressed between the fingers 

 nothing is squeezed out but a little serosity, without their 

 suffering much diminution. At first view, we are puzzled 

 to explain this disorganization : we, however, by means of 



