Meteorology of New Haven. 



245 



The average results for the two series of years preceding and fol- 

 lowing 1820, are as follows: 



The number of observations of the apricot is too small to afford a 

 reliable average, and moreover this tree frequently shoAvs a fcAV blos- 

 soms a full fortnight before the time of general flowering. But little 

 importance therefore is attached to these observations of the apricot. 

 For the five remaining trees the times of flowering before and since 

 1820 agree remarkably well, esj^ecially for the peach and apple, for 

 which the observations are most numerous ; and since the differences 

 for these two trees are not only small but have contrary signs, we 

 must conclude that in the temperature of spring there has been no 

 appreciable change within the past 86 years. 



If we bring together the principal results of the last three tables, 

 we shall more readily perceive their bearing upon the question of 

 permanence of climate. The following table exhibits the most im- 

 portant results. 



The differences betAveen the two series of observations, as shown 

 in the last column, are sometimes positive and sometimes negative ; 

 the average of all the differences being negative, and amounting to 

 not quite one-third of a day. 



When we consider that the observations which are here compared 

 were made by more than twenty different persons, without concert 

 and without any uniform system of observation ; that the subjects of 

 observation are in their very nature somewhat indefinite ; and that 

 many of these records were casually made without any idea that 

 special importance would ever be attached to them ; we must admit 

 that the small discrepancy of one-third of a day may have resulted 

 from the want of uniformity in the system of observations, without 

 implying the slightest permanent change in the character of our 

 climate. 



