SYMPTOMS. 501 



febrile symptoms seem to maintain a distinct corelation to 

 each otlier, this corelation being a disturbance of that which 

 naturally subsists between the temperature, the frequency of 

 the pulse, and the respirations. When cough exists, which 

 is not always the case, it is at first dr}^, after some time 

 becoming less so from the exudation which is taking place 

 in connection with the bronchial and pulmonic structures. 

 We do not, as in man, find much expectorated material to 

 assist us in forming aii opinion as to the condition of the lung- 

 tissue and air-conduits. 



When gangrene and disintegration of tissue occur we have 

 full indications of such, chiefly from the foetor of the breath, 

 and it may be also from the debris of the structures undergoing 

 removal being mingled with the matter expectorated. 



During the continuance of fever in a high degree the urinary 

 secretion is greatly lessened in amount, and altered in com- 

 position. There is excess of urea, probably the direct result of 

 active tissue-change, also a diminution of the salines, markedly 

 of the chloride of sodium ; this is a feature particularly noticed 

 by observers of pneumonic inflammation in man, and I have 

 observed it in the horse, although I cannot affirm that in his 

 case it is in direct relation to the state of resolution, or regard 

 its reappearance in the urine as a certain symptom of returning 

 health, or restoration of lung-function. The bowels are rather 

 torpid as a rule, but of such a character as to bo very suscep- 

 tible of being acted upon by purgative agents. 



2. Local. — In addition to these general symptoms, those 

 which are regarded as the truly physical signs are in every 

 instance deserving of careful observation and study, seeing that, 

 apart from the assistance which they render us, the differing 

 changes of structure might pass unappreciated. The sounds 

 detected by auscultation, and elicitated by percussion, are 

 both of them in inflammation of the lung-substance much 

 modified. 



During the earlier stages, those of arterial irritation and 

 that of turgescence, auscultation reveals to us a condition at 

 first of rather increased and harsh respiratory murmur, to be 

 succeeded by weakening of the normal sound ; while as 

 eftusion takes place, the respiratory murmur, however altered, 

 is replaced by minute crepitation, the true 'crepitant rale.' 



