14 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 63 



By experiments on the mucous membrane of the dorsal wall of the 

 pharynx, Thomson and Hewlet found that a particle of wet cork was 

 conveyed at the rate of 25 mm. or one inch per minute. 



Wurtz and Lermoyez have published researches on the action of 

 nasal mucus upon the anthrax bacillus and they hold that it exerts 

 a bactericidal influence on all or nearly all pathogenic agents in dif- 

 ferent degrees of intensity. 



Thomson and Hewlet corroborate this to the extent of saying 

 that the nasal mucus " is possessed of the important property of 

 exerting an inhibitory action on the growth of micro-organisms." 

 Their experiments upon each other were very ingenious and highly 

 interesting. They were able to demonstrate that in ordinary air of 

 the laboratory under the conditions observed, 29 moulds and nine 

 bacterial colonies developed ; whereas after passing through the nose 

 the air contained only two moulds and no bacteria. 



On another occasion they found in nine liters of laboratory air, 

 six moulds and four bacterial colonies, while the same quantity of 

 air after passing through the nose exhibited one mould and no bac- 

 teria. Thus they show that practically all, or nearly all, the micro- 

 organisms of the air are arrested before reaching the naso-pharynx ; 

 probably a majority are stopped by the vibrissse at the very entrance 

 to the nose and those which do penetrate as far as the mucous 

 membrane are rapidly eliminated. They state that the nasal mucus 

 is an unfavorable soil for the growth of organisms and in this it is 

 aided by the ciliated epithelium and lacrymal secretion. 



COMPOSITION OF EXPIRED AIR 



Dr. D. H. Bergey in 1893-4 made some experiments in the Labor- 

 atory of Hygiene of the University of Pennsylvania under the pro- 

 visions of the Hodgkins Fund of the Smithsonian Institution which 

 are pertinent to this subject.^ These were conducted to ascertain 

 whether the condensed moisture of air expired by men in ordinary, 

 quiet respiration, contains any particulate organic matters, such as 

 micro-organisms, epithelial scales, etc. The expired breath was con- 

 ducted through melted gelatin contained in a half liter Erlenmayer 

 flask, for twenty to thirty minutes. The gelatin was then hardened 



'J. S. Billings, S. Weir Mitchell, and D. H. Bergey: The Composition of 

 Expired Air and Its Effects on Animal Life. Smithsonian Contributions to 

 Knowledge, Vol. 29 (Publication 989), Washington, 1895. This investigation 

 seemed to disprove the renowned experiments of Brown-Sequard and D'Ar- 

 sonval in 1887. 



