SUCCESSION. 537 



only useful when gaseous and liquid matters co-exist in the 

 pleura ; in such cases, however, a splashing or churning sound 

 may be heard. It will strike every one that this measure 

 is only applicable to the smallest class of animals. 



DISEASES OF THE RESPIRATORY ORGANS. 



The diseases of the respiratory organs prevail to a large 

 extent in this country, and may be classified under two heads, 

 the local and non-contagious, the general and contagious. 

 I mean by local, more particularly, the affections of some 

 part of the respiratory apparatus due to a cause operating 

 on it locally; any systemic disturbance being a secondary 

 result. The general and contagious class includes malignant 

 forms of angina and pleuro-pneumonia in which the local 

 manifestations are but secondary, and dependent on causes 

 which operate on the system generally. 



The local and non-contagious disorders above mentioned 

 may be divided into acute and chronic, but more commonly 

 they are considered in the order of succession suggested by 

 the relation to each other of the part affected, beginning with 

 the nose, and passing on to the larynx, trachea, bronchial 

 tubes, lungs, and pleura. I shall reserve as a distinct section 

 of this subject, to be considered after the local disorders, the 

 various affections which are due to organic changes, the 

 results of injury or otherwise, and which are characterised by 

 difficult breathing or dyspnoea. Under this head I shall 

 include roaring, asthma, and broken wind. 



DISEASES OF THE NOSE. 

 EPISTAXIS, OK HAEMORRHAGE FROM THE NOSE. 

 The discharge of blood from the membrane lining the 

 nose is usually a symptom rather than a special disease. It 



