APPENDIX I 



TEMPERATURE DEPARTURES FOR FORTY-SEVEN INLAND 

 STATIONS, 1875-1910 



Communicated by C. G. Abbot 



director, smithsonian astrophysical observatory 



In Volume 2 of Annals of the Astrophysical Observatory of the 

 Smithsonian Institution (Washington, 1908) an investigation of 

 temperature departures was made with a view to see if notable 

 anomalies occurred simultaneously and generally over the earth, such 

 as might reasonably be ascribed to solar variations. At about the 

 same time Professor Simon Newcomb published ^ an investigation 

 with a similar aim. These investigations differed radically in method. 



In the Smithsonian investigation care was taken to exclude coast 

 and island stations, and to employ inland stations as uniformly dis- 

 tributed over the continents as the observational data allowed. 

 Stations under oceanic influence or control, though their records 

 were of longer standing and generally more accurate, were thought 

 unsuitable, because the temperature efifects of short interval solar 

 changes, if such there are, would be greatly reduced at such stations. 

 Furthermore, being unequally retarded, they would be non-syn- 

 chronous, so that in a general mean they might altogether disappear. 

 Ordinary graphical methods of exposing the results were employed. 

 The stations were combined in groups according to location. Aver- 

 age departures and probable errors for these groups were computed 

 in the usual way. The group results were combined into a grand 

 average and probable error, and all these results were plotted as 

 functions of time, from 1875 ^o IQ^S- 



In Professor Newcomb's work the stations employed were mostly 

 of an island or coast character. To illustrate how thoroughly some 

 were under oceanic control, among them was Apia, Samoa, where 

 the seasonal change from winter to summer ranges but i°.i centi- 

 grade, as compared with 14°. 2 at Timbuktu and generally about 

 6° range at most inland stations where equal yearly changes of 

 insolation outside the atmosphere occur. In his discussion Pro- 

 fessor Newcomb devised and employed a very ingenious mathemati- 



^ Trans. Amer. Phil. See. Philadelphia, Vol. 21, 1908. 



307 



