l6o SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



no particular influence to produce great variations in the tempera- 

 ture of the earth except in quite exceptional cases like the Krakatao 

 outbreak. 



In the tropics, he believes, the temperature variations are de- 

 veloped most regularly, merely under the influence of variations in 

 the solar activity without the disturbing influence of atmospheric 

 circulation. Indeed, by a comparison of temperature curves for 

 Arequipa, Peru, with the curve of the observed value for the " solar 

 constant " according to measures in Washington, 1903 to 1907, he 

 believes that he has shown a correlation between variations in the 

 monthly mean temperature and the observed short period variations 

 of the " solar constant " (1912, p. 603). 



By comparing the monthly mean of the fluctuating values of the 

 " solar constant " found on Mt. Wilson in the years 1905 and 1906 

 with the monthly mean temperatures for Arequipa for the same 

 months, Arctowski found it probable that an anomaly of 1° F. of 

 the monthly temperature for Arequipa corresponds to an anomaly of 

 about 0.015 calo'rie for the " solar constant." The extreme values 

 of the " solar constant," which were found on Mt. Wilson in these 

 measurements were 1.93 and 2.14 calories per square centimeter per 

 minute outside the earth's atmosphere.^ 



Plainly misled by Abbot and Fowle, who in their work in the year 

 1907 showed it probable that the temperature variations of the earth 

 march directly with variations in the solar radiation, Arctowski came 

 to the conclusion that the temperature of the earth, particularly in 

 the tropics, varies directly as the solar radiation. In their later work 

 (1913-a) Abbot and Fowle have, however, shown that they were 

 probably in error in this view and that the " solar constant " is smaller 

 at sun spot minimum than at sun spot maximum, therefore 

 Arctowski's view would be untenable. In his latest paper (1915) 

 he appears like Huntington to attribute a greater influence to the 

 atmospheric circulation. Particularly interesting are Arctowski's 

 studies of his pleions and antipleions (1909, 1910, and 1914), which 

 he finds may be perpetuated over several years with the centers of 

 the pleions traveling from year to year to and fro in irregular curves. 



We have shown (1909, p. 214) that the winter temperature from 

 1st of November to 30th of April in Norway, at Ona Lighthouse for 

 the years 1874 to 1907 changes in the same way as the sun spots so 



^In a late publication of Abbot, Fowle, and Aldrich (1913-a) these numeri- 

 cal values are diminished by 5 per cent owing to improvements in pyrhelio- 

 metry. 



