CHAPTER V. 



RESPIRATORY ORGANS. 



Their Diseases and How to Cure Them. 



Description op organs' of thoracic cavity, diseases op the nos- 

 trils, THE NASAL CHAMBERS, THE SINUSES, THE PHARYNX, THE 

 LARYNX, THE WIND-PIPE, THE BRONCHI, THE BRONCHIAL TUBES, 

 AIR-CELLS, PLEURA, AND DIAPHRAGM. 



^ ESPIRATORY organs are those that are used for, or aid in 



^f breathing. Some of the organs are used almost entirely in the 

 \^ process of breathing, while others serve a double function. The 



g) taking or drawing in of the air into the lungs is called inspiration. 

 The side walls and front of the chest move upward and outward forming 

 a vacuum and the air rushes in to fill the cavity. The sending of air 

 out of the lungs is called expiration. This is ordinarily accomplished 

 by the weight of the chest, which sinks down, displacing the air. 



Description of the Respiratory Organs. The organs aid- 

 ing in respiration may be classed as follows: 



NOSTRIIyS — the nasal openings, the place where the skin gradually 

 changes to mucous membrane; 



NASAIy CHAMBERS — the cavities through which the air passes to 

 the head. These chambers are completely separated, the right from the 

 left, by partitions of cartilage; 



SINUSES — the compartments which communicate with the nasal 

 chambers and are lined with a continuation of the same membrane; 



