218 



EIGHTEENTH ANNUAL REPORT ON THE STATE CABINET. 



The mean annual temperature of 



Latitude. Feet. Years. 



Rochefter, 43° 07' 5 16 above the Tea. 28 



Albany 42 31 130 «' 24 



Potfdam 44 40 394 " 23 



City of New- York .... 40 42 22 '* 32 



London, England 5^3* *' 53 



Wafliington, D.C 3^ 53 5^ '* 12 



Fort Sullivan, Maine . . 44 54 70 " 70 



State of New-York, from all the two means 25? 



Other results follow. 



Mean. 

 47°.02 

 48.43 



43-61 



51-54 

 48.50 



56.14 



48 .02 



46.74 to 



46.92 



Table III : Range of Half-monthTy and Monthly Means for the 28 years. 



Month. 



First half, and its mean of 



Second half, and mean of 



Month, and mean of 2S 



year*. 





28 years. 





2-i years. 











000 







000 







000 







Jan. 



15.9 to 36.7=20.8 



25.92 



13.0 to 34.8=21.8 



25.23 



15.0 to 31.8=16.8 



25.5 



Feb. 



13.5 to 35.1=21.6 



24.24 



12.1 to 38.0^25.9 



27.19 



15.2 to 33.6=18.4 



25.7 



Mar. 



19.3 to 40.2=20.9 



30.14 



23.6 to 41.4=17.8 



34.36 



22.0 to 39 4=17.4 



32.3 : 



April 



35.2 to 53.0=17.8 



40.97 



37.7 to 54.7=17.0 



46.94 



37.6 to 52.9=15.3 



43.9 



May 



45.0 to 61.4=16.4 



53.00 



51.7 to 65.9=14.2 



59.05 



51.3 to 61.8= 9.5 



56.3 ' 



June 



56.1 to 70.6=14.5 



63.13 



61.3 to 77.7=15.4 



69.00 



59.6 to 71.9=12.3 



66.0 



July 



65.7 to 74.5= 8.8 



70.25 



67.7 to 76.9= 9.2 



71.04 



66.7 to 74.8= 8.1 



70.6 



Aug. 



64.3 to 76.1=11.8 



70.12 



63.3 to 71.5= 8.2 



67.23 



65.5 to 71.1= 5.6 



68.6 



Sept. 



57.1 to 72.1=15.0 



63.83 



52.4 to 60.6= 8.2 



56.88 



57.3 to 65.4= 8.1 



60.4 



Oct. 



46.6 to 58.0=11.4 



51.32 



38.5 to 52.6=14.1 



45.08 



43.4 to 63.7=10.3 



48.1 



Nov. 



30.8 to 50.0=19.2 



41.22 



27.0 to 42.6=15.6 



34.86 



32.7 to 46.3=13.6 



38.0 



Dec. 



22.9 to 37.7=14.8 

 Mean 



39.96 



18.8 to 32.6=13.8 

 Mean 



25.73 



22.5 to 34.3=11.8 

 Mean 



28.6 



47.09 



46.88 



47.0 



The mean of the monthly means of the first half of the months, 47°. 09, 

 a little exceeds, and of the second half, 46°. 88, falls a little below, the mean 

 of the months, 47°. 0. It is curious that the mean temperature of the two 

 halves of the months differs so very little from the mean of the months. 



In this Table, the diiference in the means appears greater in the colder 

 months than in the warmer months. This is chiefly owing to the fact that 

 in the colder months the morning observations, and in part the evening 

 observations also, are made at an hour nearer to the colder or coldest part 

 of the day. Then, too, it is not consecutive temperature that is shown in 

 these highest and lowest means of half-months in these 28 years. Thus we 

 see, looking at the table for the first half of January, that the range of these 

 half-monthly means is from 15°. 9 to 36°. 7, or 20°. 8. Yet we may see in 

 Table 11 that 15°. 9 was the mean of this first half of January 1836, and 

 36°. 7 belonged to 1838. So also the lowest and highest means of the means 

 of the first half of July in the 28 years belonged to different years, 65°. 7 

 in Table iii to 1860, and 74°. 5 to 1838; and here the range of the highest 

 and lowest is only 8°. 8. 



This Table shows that the temperature of July is more equable than in 

 any other month : the mean heat of the first half of July is 70°. 25, and of 

 the last half is 71°. 04 ; or the means of the two halves for 28 years diflPer 

 only four-fifths of a degree. August is the next month for equableness of 

 temperature, and June is next to that. 



The greatest difference in the means in Table iii occurs in the last half 

 of February ; 12°. 1 in 1838 being excessively low, and 38°. in 1857 being 

 the other great extreme for the season. 



