318 METEOROLOGY. 



A table, [lo], of use for the reduction of observations for temperai!; 

 ture of the air in the shade, made at different hours of the day by thi 

 formula 



ig. The observed temperature. 



t^. The mean of the 24/i. 



p. A factor depending on the disposition of the atmosj)here for solai 

 heat, the mean factor of the month being unit. 



p w. The correction to the mean temperature of the day to get ou 

 the observed one. 



t^ and p are to be found for each day by the method of least squares' 

 or by a good approximation to it, by a calculation shown on the next 

 page. 



