266 



HITCHCOCK'S ANATOMY 



liable to disease, and consequently need especial care to keep 

 them in health. 



469. — 3. Action of the Lungs Essential for their 

 Health. — One important item to secure the health of these 

 organs, is to keep every part of them in action. Hence pres- 

 sure of clothing, or any thing else that prevents the complete 

 filling of the lungs by breathing, is quite sure to induce dis- 

 ease. For if but a very few of the millions of air-cells con- 

 tained in the lungs are allowed to lie inactive or useless, na- 

 ture will attempt their removal by means of the lymphatics, 

 and this removal is often the commencement of fatal disease. 

 Therefore it is a good practice for every one, and especially 

 sedentary persons, several times each day to throw back and 

 downwards the shoulders, and slowly fill the lungs to their 

 utmost capacity, and then permit the air to escape slowly, be- 

 cause in this way every cell in the lungs will be used. 



470. — 4. Pure Air is Essential to Healthy Lungs — 

 Life Depends on Breathing Pure Air.* — All mechanical 

 and chemical impurities of the air inhaled induce and ag- 

 gravate disease. Indeed, the most important hygienic rule 

 for the lungs is to breathe pure air. Mechanical impurities, 

 such as dust and vapors, are eminently injurious, but not so 

 much so as the chemical impurity, carbonic acid, which comes 

 from the exhalations of men and animals, and the burning of 



Black Holt, or Calcutta. — One of the most awful instances of suffocation on rec- 

 ord, is connected with what is known as the Black Hole of Calcutta. When Calcutta 

 was taken by the Indian forces, the British garrison, numbering 146 men, were confined 

 as prisoners of war in the dungeon of the fortress, a room only eighteen feet square, and 

 intended only for confinement of two or three men. This dungeon had only two small 

 ■windows, both upon one side of the building, in front of which was a verandah that aided 

 greatly in impeding whatever slight circulation of air there might be. Besides the great 

 heat of a July night, on which this occurred, conflagrations were raging near the fort 

 which greatly increased the heat. Very soon after the men were confined, the suffering 

 became intolerable, and the dungeon was a scene not only of the intensest anguish, but 

 of frightful delirium of most of the inmates. By eleven oVlock the men began to die 

 very rapidly, and owing to the intense heat and overpowering stench caused by these 

 exertions of the frantic soldiers, in the morning at six o'clock, when the doors were 

 opened, but twenty-three were alive, who were either stupefied or raving. 



468. What does their delicate structure show us? 469. What is said of the necessity 

 of action for the lungs ? What habit is of great service, and why is it ? 470. How do im- 

 purities of the air affect the lungs? What kind of impurities are the most injurious? 

 What is one of the principal sources of disease in civilized society ? 



