502 PNEUMONIA. 



This sound much resembles what wc have ah'eady remarked as 

 occurring in cases of capillary bronchitis, but does not, as there, 

 continue or become modified according to the amount and 

 nature of the mucus secreted and found in the tubes. After 

 a little, as the air-cells and surrounding connective-tissue 

 become infiltrated, the crepitation ceases not again to be heard 

 until a return to health has been established. As the engorge- 

 ment or effusion into, and consolidation of, lung-structure 

 progresses, and the natural respiratory murmur ceases, the 

 characteristic bronchial respiration appears, and this tubular 

 or bronchial sound is the more distinct, the more complete 

 consolidation of the pulmonic tissue becomes. 



Seeing that in pneumonic inflammation we rarely, by per- 

 cussion over the seat of the disease, are able to obtain aught 

 more definite than a slight amount of dulness, or want of 

 resonance, even Avhen, from other symptoms, we may be 

 tolerably certain that the pulmonary tissue is much diseased, 

 we can only look upon this as valuable in corroborating what 

 we learn by auscultation. 



However, when forming our opinion with respect to the 

 existence of pneumonia, it is well, if we would endeavour to 

 avoid mistakes, not to lean too implicitly on any one symptom 

 or class of symptoms, but to observe that each one corroborates 

 the others; to note whether the general symptoms, which 

 usually first attract attention, are confirmed by what may be 

 learned from a physical examination of the chest. 



Course and Termination. — Ordinary cases of pneumonia, even 

 those which are complicated with a considerable amount of 

 bronchitis, usually reach the height of the pyrexia in a week, 

 or little more, taking a somewhat longer period ere resolution 

 is well established. 



Although we have noted the different pathological changes 

 which lung-tissue usually undergoes, it ought also to be 

 remembered that all these various changes of structure are not 

 necessarily accomplished or gone through in every case ere 

 restoration to health is established. Very many, probably the 

 greater number of those which recover, have proceeded no 

 further than the entrance of the territory of true inflammatory 

 action, the beginning of the stage of red hepatization ; others, 

 no doubt, have not only proceeded to consolidation of lung- 



