52 



Composition of the Atmosphere 



land and Ward, 1 in which the hydrogen-explosion method is employed. 

 Most of the samples were analyzed in duplicate, the difference at times 

 being 0.05 per cent. An abstract of his results is given in table 35. 



The most noteworthy observations in this series are the extremely low 

 values occasionally found for oxygen. On this point Morley says : 



On Sept. 16, 1878, two very careful analyses of the same sample gave 20.49 and 20.46 

 per cent of oxygen. * * * Within the time covered by the analyses now published, 

 there were several well-marked great and sudden depressions of temperature, and the fig- 

 ures show the falling off in the proportion of oxygen in the air at these times to be as well 

 marked as the depression of temperature. The deficiency is not proportionate to the de- 

 pression of temperature ; this could not be expected. 



In a second communication, 2 Morley reports a very large number of 

 analyses made with even greater care, comparing the results with the 

 meteorological conditions which existed at the time. The investigation 

 extended from January 1, 1880, to April 20, 1881, analyses being made 

 nearly every day except during the vacation months of July, August, and 

 September 1880. Usually duplicate analyses of the same sample were 

 made and occasionally several samples were taken on the same day. For 

 painstaking care and extent the work is marvelously complete. A part 

 of his results are given in table 36, these being fairly indicative of the ac- 

 curacy of the work, and the agreement of duplicate analyses. 



Table 36. Determinations of oxygen in atmospheric air made by Morley. 



While Professor Morley cites numerous instances of meteorological 

 conditions accompanied by decreases in oxygen which are consistent with 

 his hypothesis, there are fully as many days of low oxygen when he ad- 

 mittedly is unable to explain the fall as a result of meteorological change. 

 Furthermore, he repeatedly cites falls in oxygen amounting to but 0.01 

 per cent as significant. Morley concludes that there is no connection 

 between the deficiencies in oxygen and the direction of the wind at the 



1 Frankland and Ward, Quart. Journ. Chem. Soc. (London), 1854, 6, p. 197. 



2 Morley, American Journal of Science, 1881 (3), 22, p. 417. 



