DISEASES OF POULTRY. 265 



that the disease is infectious. Let the mouth and 

 beak be washed with a weak solution of chloride of 

 lime. 



INFLAMMATION OF THE LUNGS. 



FOWLS, in a state of health, rarely breathe through 

 the mouth as we do, but almost always through the 

 nostrils, which are comparatively large, and communi- 

 cate backward with the top of the windpipe. The 

 windpipe itself is composed of stiff rings of cartilage, 

 united by strong membranes ; and such is the elasticity 

 of these, that the tube is enabled to preserve its cylin- 

 drical form, even when it receives considerable pres- 

 sure, and thereby affords free ingress and egress to the 

 air in breathing. 



When the windpipe descends into the chest, it di- 

 vides into numerous branches called the " bronchial 

 tubes," which gradually becoming smaller, at length 

 terminate in perforations, but neither these branches 

 nor the cells are so small in fowls as in other animals. 

 It is these branchings of the windpipe, however, which, 

 together with numerous blood vessels, make up the 

 substance of the lungs, the interstices being filled with 

 a fine membrane that serves not only to unite them, 

 but likewise to give a uniform appearance to the whole 

 mass. The perforations in which the branches of the 

 windpipe terminate, lead into large air sacks com- 

 municating with all parts of the body, and forming an 

 accessary lung. 



With reference to a not uncommon disorder among 

 fowls, it is important to mention that the lungs are 

 covered with a fine delicate membrane called the 

 pleura, on every part of which a watery fluid is secre- 

 ted, for. the purpose of preventing a cohesion of the 

 parts. 



Inflammation of the lungs, including the bronchial 

 tubes, is not uncommon in fowls. Its symptoms are 

 quick breathing, often with a rattle, or rale, very 

 12 



