Meteorology of Xeic Hctven. 



229 



Corrections to be applied to the means of the hours of observation to 

 obtain the true mean temperatures at New Haven. 



Having obtained the means of reducing observations made at ir- 

 regular hours to fixed hours, we next undertook a more satisfactory 

 reduction of the entire series of observations embracing 86 years. 

 Taking the January series, we computed from the preceding table, 

 the reduction for each of the morning observations to 7 o'clock, and 

 finding the mean of the Mdiole, we obtained the average temperature 

 at < o'clock according to 86 years of observations. Each of the mid- 

 day observations was in like manner reduced to 2 o'clock, and finding 

 the mean of the whole, we obtained the average temperature at 2 

 o'clock. In the same manner, each of the evening observations was 

 reduced to 9 o'clock, and the mean of the entire series was taken. 

 The observations of each of the other months were in like manner 

 reduced to the nearest even hour. 



"We next took the series of observations made five times a day, 

 embracing a period of nine years, and reduced each of them in like 

 manner to the nearest even hour. We then took the difference be- 

 tween the averages for the morning and mid-day observations in the 

 long and short series, and applied half the sum of these differences 

 as a correction to the 10 o'clock observation, by which means Ave ob- 

 tained the most probable temperature at 10 o'clock corresponding to 



