206 RESPIRATION 



giving larger space and air-supply; and as a consequence, 

 the mortality from consumption has diminished more than 

 one-third. 



38. The lower animals confined in the impure atmosphere 

 of menageries, contract the same diseases as man. Those 

 brought from a tropical climate, and requiring to be closely 

 housed, generally die of consumption. In the Zoological 

 Gardens of Paris, this disease affected nearly all monkeys, 

 until care was taken to introduce fresh air by ventilation, and 

 then it almost wholly disappeared. The tendency of certain 

 occupations to shorten life is well known, disease being occa- 

 sioned by the fumes and dust which arise from the materials 

 employed, in addition to the bad air of the workshop or 

 factory, where many hours are passed- daily. (Read Note 9.) 



39. The following table shows the comparative amount of 

 carbonic acid gas in the air under different conditions, and the 

 effects sometimes produced : 



PROPORTION OF CARBONIC ACID GAS. In 1000 parts of Air. 



Air of country 4 



Air of city 5 



In hospital, well ventilated 6 



In school, church, etc., fairly ventilated . . . 1.2 to 2.5 

 In court-house, factory, etc., without ventilation 4. to 40. 



In bed-room, before being aired 4.5 



In bed-room, after being aired 1.5 



Constantly breathed, causing ill health .... 2. 

 Occasionally breathed, causing discomfort ... 3. 

 Occasionally breathed, causing distress .... 10. 



Expired air 40. 



Air no longer yielding oxygen 100. 



9. Consumption is Lung Starvation. " The practice of allowing the 

 lungs only improper food, in the form of vitiated air, is one of the most 

 prevalent habits of civilized life, and diseases of the lungs are its greatest 

 bane and greatest dread. More persons die by consumption than by any 

 other single disease. If there be added to those the large number that 

 perish every year by inflammation of the lungs and bronchial tubes, disease 

 and premature death may be well said to have in these organs their chief 



38. How, in the case of the lower animals ? Tendency of certain occupations ? 



39. Give the fact & set forth in the table. 



