34 



Composition of the Atmosphere 



epidemic are reported in the literature, 1 i.e., those of Baumgartner 2 and 

 Laskowsky. 3 



Employing Brunner's method, Laskowsky in Moscow made a num- 

 ber of analyses of air during the cholera epidemic. The results, which 

 are given in table 11, show a variation of 0.16 per cent of oxygen, which the 

 author maintains is not far from the results of Dumas and Boussingault, 

 who report variations of 0.19 per cent. He concludes that the air in 

 Moscow during the time of the cholera was normal. 



Table 11. Air-analyses made by Laskowsky in Moscow during the cholera in 1847. 



Adding oxide of manganese to the reduced copper of the Dumas and 

 Boussingault method to increase its absorbing action, Deville and Gran- 

 deau 4 determined the oxygen in a number of samples of air for May and 

 June of 1859, and found as an average 20.88 per cent. 



An ingenious use of an ammoniacal solution of copper chloride as an 

 absorbent for oxygen was made by Doyere 5 in connection with studies 

 on respiration. As the result of several analyses by this and other meth- 

 ods, Doyere reports that the percentage of oxygen in air is about 20.5 to 

 20.7, but the research does not inspire confidence. 



Employing an exceptionally accurate hydrogen eudiometer designed 

 primarily for use in their classical respiration experiments, Regnault and 

 Reiset reported in a preliminary communication in 1848 6 a large number 

 of analyses that were made during the three preceding years, 1845, 1846> 

 and 1847, in Paris, as well as near Dieppe. All of these analyses showed 

 an oxygen content between 20.85 and 20.97 per cent. In the report of 

 their experiments on the respiration of animals, 7 the authors give a com- 



1 The early observations of Davidson, who found 67 per cent of vital air in Mar- 

 tinique during an epidemic of yellow fever, are only of historic interest. (Cited by 

 Russell, Transactions of the Sanitary Institute, 1893, 13, p. 232.) 



2 Baumgartner, loc. cit. 



3 Laskowsky, Liebig's Annalen der Chemie und Pharmacie, 1S50, 75, p. 176. 



4 Deville and Grandeau, Comptes rendus, 1859, 48, p. 1103. 



5 Doyere, Annates de Chimie et de Physique, 1850, 3d ser., 28, p. 5. Among the 

 innumerable observations on the composition of the air made by Scheele, it is interesting 

 to note that he found that one-third of the air was absorbed by an ammoniacal solution 

 of copper. (See Scheele, Efterlemnade bref och anteckningar. Edited by A. E. Nor- 

 denskiold, Stockholm, 1892, p. 58.) 



6 Regnault and Reiset, Comptes rendus, 1848, 26, p. 6. 



7 Regnault and Reiset, Annales de Chimie et de Physique, 184S, 3d ser., 26, p. 299. 



