OF THE ATMOSPHERIC TEMPERATURE. 



315 



the spotted surface as contrasted with the whole sun, the faikire in the detection 

 of any close relationship between the annual changes of spots and of terrestrial 

 temperature (as examined by the comparatively crude process of annual means) 

 should not be surprising, unless there should be connected with these solar disturb- 

 ances some other less direct cause producing changes of radiation. Still it is very 

 desirable to follow up the subject by further comparisons of the American results 

 with those obtained on the Eastern Continent, and especially with results from 

 stations in the Southern Hemisphere.^ 



Comparison of the secular variation in the temperature and the rain-fall, in the 

 United States. — The data for the annual rain-fall are taken from p. 154 of my 

 memoir on the Rain-Fall (Smithsonian Contributions to Knowledge, No. 222 ; 

 Washington, May, 1872), from which groups I and IV have been selected as 

 representative stations of the same climatological conditions to which the tempera- 

 ture types I and II refer. The fourth order of successive means are tabulated 

 below; these proportional numbers have already been charted on p. 157 of the Rain- 

 Fall Memoir. The average annual amount of rain deduced from the whole series 

 is put equal to 100. 



Secular variation in the Rain- Fall, sea-coast, Maine to Virginia. 









I 



2 



3 



4 



5 



6 



7 



8 



9 



i8oo 





















(94) 



96 



102 



io6 



lOI 



i8io 



94 



96 



lOI 



104 



103 



97 



92 



90 



87 



87 



1820 



93 



94 



96 



97 



94 



89 



91 



96 



102 



108 



1830 



III 



108 



104 



99 



94 



91 



90 



90 



93 



98 



1840 



103 



105 



106 



103 



98 



96 



100 



102 



99 



100 



1850 



105 



106 



105 



loS 



102 



98 



98 



102 



106 



108 



i860 



108 



108 



III 



no 



106 



104 



(107) 









Secular change in the Rain-Fall, Ohio Valley, Ohio, Indiana, Illinois, Kentucky, and 2^ art of 



Missouri. 









I 



2 



3 



4 



5 



6 



7 



8 



9 



1810 







































(96) 



1820 



95 



100 



105 



107 



106 



104 



103 



103 



102 



97 



1830 



95 



lOI 



102 



97 



93 



93 



93 



89 



84 



86 



1840 



92 



95 



98 



99 



100 



104 



no 



114 



113 



no 



1850 



106 



102 



97 



93 



93 



94 



92, 



99 



109 



109 



i860 



103 



lOI 



99 



95 



93 



97 



(i°3) 









^ To mention but one case of evidence, supposed to be in favor of a correspondence of the sun- 

 spot and temperature periods, the reader may consult : The London, Edinburgh, and Dublin Phil. 

 Mag., vol. xlii, July to Dec. 18*71. "On the approximate decennial variation of the temperature 

 at the Observatory at the Cape of Good Hope, between the years 1841 and 1870, viewed in connec- 

 tion with the variation of the solar-spots." By E. J. Stone, F.R.S, Astron. Roy. at the Cape of 

 Good Hope. Here it is believed that the same cause which leads to an excess of mean annual 

 temperature leads equally to a dissipation of the solar spots. 



