NO. 2?, INFLUENCE OF ATMOSPHERE ON HEALTH 29 



We will now summarize the evidence for and against the existence 

 of an organic chemical poison in expired air. 



Hammond 1 arranged an experiment in which a mouse was en- 

 closed in a large jar with sponges soaked in baryta to absorb the 

 exhaled C0 2 , etc., and he attributed the death of the mouse to 

 organic poison. His method undoubtedly was at fault, the mouse 

 dying of suffocation. 



Ransome ' condensed the aqueous vapor of human breath and 

 found that " in ordinary respiration about 0.2 of a gramme or 3 grs. 

 of organic matter is given off from a man's lungs in 24 hours," and 

 that this amount varies greatly in certain diseases ; for example, it 

 is greatest in a ease of phthisis complicated with Bright's disease. 



Seegen and Nowak J demonstrated, as they thought, the presence 

 of poisonous organic matter in the expired air, but the quantity 

 obtained was so small that its nature and properties could not be 

 determined. 



Hermans 4 was unable to detect any organic matter in the atmos- 

 phere of the small chamber in which he confined persons for many- 

 hours. 



The widespread belief in the presence of organic poisons in the 

 expired air is mainly based on the statements of Brown-Sequard and 

 D'Arsonval, almost wholly unsubstantiated by other workers. These 

 statements have done very great mischief to the cause of hygiene, 

 for they have led ventilating engineers to seek after chemical purity, 

 and neglect the attainment of adequate coolness and movement of 

 the air. 



In their first series of experiments Brown-Sequard and D'Arsonval 

 injected into the blood-vessels of a rabbit water with which they had 

 repeatedly washed out the air-tubes of a dog". In a second series they 

 injected the water condensed from the exhaled breath of man; in a 

 third series, the water condensed from the exhaled breath of a 

 tracheotomized dog. 



The symptoms recorded 5 were dilatation of the pupil, acceleration 

 of the heart, slowing of the respiration ; there usually occurred 

 diarrhoea and paralysis of the posterior limbs. The larger doses 

 caused, as a rule, labored breathing, retching, and contracted pupils. 



1 A Treatise on Hygiene. Philadelphia, 1863. Cited after Billings, etc. 

 ' Journ. Anat. and Physiol. London, 1870, Vol. 4, p. 209. 



3 Arch. d. ges. Physiol. Bonn, 1879, Vol. 19, p. 347. 



4 Cited supra. 



5 C6mpt. Rend. Soc. de Biol, 1887 (8), iv, 814; 1888 (8), v, 33, 54, 94, 10N. 

 121 ; Compt. Rend. Acad. d. Sc, Paris, Vol. 106, 1888, p. 106. 



