ACUTK DISEASES OF TUL OKGANS OF KESPIRATIOX. 215 



last from twenty-four to forty-eight hours, at the end of which time a 

 decided change for better or worse wiU occur. During this time the 

 breathing will become quicker on account of the increasing congestion in 

 the air cells. The pulse, though still oppressed, will become weaker and 

 quicker. 



Pneumonia may attack one lung or one portion of one lung or both 

 lungs. The extent and position of the attack may be ascertained by 

 auscultation. 



433. Subsidence of the attack. 



Sulj.sidence of the attack is indicated by the return of the pulse to 

 something like its normal condition, by restoration and continuance of 

 warmth in the extremities, by a moist state of the nostrils, or the appear- 

 ance of healthy mucus, and by general relief of the symptoms of inflam- 

 mation and by a disposition to lie down. 



It is necessary, however, to caution the inexperienced against mistaking 

 the earlier symptoms of effusion of serum into the thoracic cavity for 

 those of amendment. The means of distinfmishinj; them wiU be found 

 further on under the head of Effusion in paragraph 445. 



434. Increase of the attack. 



[| If on the other hand the disease continues to progress, the mouth and 

 nose will become cold, the nostril of a leaden hue, and the pulse fluttering 

 and indistinct. The attack may terminate in effusion of sermii, otherwise 

 known as water on the chest, or in exudation of lymph from the pleural 

 surfaces (these, however, are more frequently the resvdt of pleuritis or 

 pleuro-pneumonia) in partial hepatisation of the lungs, or in tubercles, 

 abscesses, gangrene, &c. 



A very unfavorable symptom is afforded by the discharge from the 

 nose becoming of a brownish colour. It indicates a high degree of con- 

 gestion of the blood-vessels of the lungs. The change of colour proceeds 

 from oozing of the colouring matter of the blood through the over-dis- 

 tended coats of the vessels. 



Occasionally the patient dies from congestion of the lungs about the 

 4th or 5th day, or even as early as the 2nd day, before any of the latter 

 described stages are reached. 



Horses sometimes die of congestion of the lungs from hard riding or 

 from plethoric state of the system. In these cases the cause of death is 

 sanguineous congestion of the lungs, i. e. from the blood-vessels pouring 

 out some of the constituents of the blood into the air cells. 



We reserve our notice of treatment, and of after-results, until after the 

 consideration of the s'\'mptoms of the kindred diseases, Pleuritis and 



r 



