METHODS AND OBJECTS OF PHYSICAL EXAMINATION. 427 



experience is needed to use this instrument well, and to obtain 

 from it the maximmn of benefit. In cases where blistering 

 agents have been employed on the chest, its use is absolutely 

 needful and easily understood. 



Each of these methods has advantages peculiar to itself, and 

 either is perfectly efficacious when practised so that the little 

 difficulties and niceties of the art are thoroughly mastered. 

 When immediate auscultation is practised, if a handkerchief is 

 used it ought not to be doubled in case friction between the 

 two surfaces might mislead, and the ear must be placed perfectly 

 flat on the surface to which it is applied. In the employment 

 of the stethoscope, the cup-shaped extremity ought to be placed 

 evenly on the skin, and firmly maintained in its position by 

 the ear being closely applied to the larger extremity ; it should 

 not be held with the fingers. 



In all cases we should endeavour to secure for the perform- 

 ance of the operation a place perfectly free from outside noise 

 and the chance of disturbance. To increase the sounds it may 

 in some cases, prior to the examination, be advisable to give 

 the horse a little rapid exercise. In the greater number of our 

 cases the direct application of the ear to the chest is better than 

 auscultation by an intervening instrument. In this method the 

 surface covered is greater, the head is steadied by the support 

 of the animal's body, and the ear is brought nearer the objects 

 we wish to examine. 



So far as examination of the thorax is concerned, the object 

 of auscultation is to examine {a) sounds connected Avith the 

 lungs and great air-tubes ; (b) with the pleura, the so-called 

 friction-sounds ; (c) with the heart, and {d) other diseased 

 sounds connected with abnormal conditions of the chest and 

 contained organs. 



0. Succussion. — This is the act of grasping the thoracic 

 cavity between the hands, and by sharply shaking it to cause 

 agitation of its contents and so elicit sound. This is only 

 possible in small animals, and in every case has to be carefully 

 performed, not merely from the disturbance it entails upon the 

 animal, but also from the liability there is to confound sounds 

 of the thorax with those of the abdomen produced at the same 

 time. 



