CHAPTER XLVL 



SrO RADIO DIS'EAS^^— continued. 



LOCAL DlS'EA8'E&—co7itinued. 



(I.) DISEASES OF THE EESPIRATOEY OEGANS. 



Before entering upon the consideration of the particular dis- 

 eases of the respiratory organs, it will be necessary to point out 

 certain modes of physical examination by which the diagnosis 

 of these diseases is accurately traced. 



1. Auscidtation. — In its technical sense this term indicates 

 the act of listening to the sounds of the interior by means of 

 the ear applied to the surface of the body. 



Auscultation may be practised directly by applying the ear to 

 the part ; or indirectly through the medium of an instrument 

 called a stethoscope. Generally direct or immedicde answers 

 every purpose ; and in veterinary practice, at least, indirect or 

 mediate auscultation is seldom practised. Auscultation, dis- 

 covered by Laennec, was introduced into veterinary practice by 

 Delafond and Leblanc. 



Many of the sounds characteristic of abnormal conditions in 

 the human being are not heard in the lower animals; hence 

 auscultation, as well as percussion, is less satisfactory in the 

 hands of veterinary surgeons than in those of the physician. 

 There are various reasons for this, and not the least of them is 

 the fact that the thoracic walls of man are much more thinly 

 covered with muscular tissue than those of the lower animals. 

 A^ain, a large portion of the thoracic cavity in our patients is 

 covered by the scapulte, which form insuperable barriers to 

 examination. These, in addition to the movements of the 

 pannicuhis carnosus, the horizontal position of the body, oblique 

 arrangement of the diaphragm, the pressure of the digestive 



