REPORT OP THE SECRETARY. 33 



same temperature as the mean of the whole year are the 14th of 

 April and the 15th of October. 

 The average temperatures of the seasons are as follows! 



o 

 Spring 52. 88 



Summer 71.51 



Autumn 52 .78 



Winter 33.01 



There have been observed by the meteorologists of Europe varia- 

 tions in the ordinary march of the change of temperature. Of these 

 there is one about the beginning of December, and another about the 

 middle of May, which are most conspicuous. The cause of such 

 abnormal change of temperature must be either local or general; if 

 the latter, its influence must be felt, perhaps, with some modification 

 in all parts of the globe. The observations were examined in regard 

 to these abnormal changes; but though they indicate a normal 

 temperature about the beginning of December, they show a remarka- 

 ble depression of temperature between the 25th and 28th of Novem- 

 ber, which is preceded by an elevation on the 22d. A similar de- 

 pression, however, is not observed in the series for Brunswick. 



The direction of the wind is recorded for 27 years to eight points 

 of the compass, and the result as to the relative frequency of each 

 in proportion to 1,000 is shown in the following table: 



From this it appears that the majority of the winds are from the 

 north and southwest, while the northeast and east winds are the least 

 frequent. The south wind is more frequent in summer, and the west 

 and northwest in winter. This differs slightly from the winds in 

 Brunswick, Maine, where the wind of the greatest frequency is that 

 from the northwest, and next from the southwest. The difference is 

 probably due principally to the configuration of the surface. 



The result of another investigation indicates an apparent secular 

 change in the direction of the wind, similar to the one noted at Bruns- 

 wick; but as the epochs are different, the subject requires the discus- 

 sion of more extended observations at different places. 



The discussion of the connection of the direction of the wind with 



3SG7 



