32 



RESULTS or METEOROLOGICAL OBSER VAT TONS 



May, with May .94 of the first of June, with June the first and .37 of the second 

 of July, with July .81 of the first of August, with August .25 of the first of Sep- 

 tember, with September .69 of the first of October, with October .13 of the first of 

 November, and with November .56 of the first of December.^ It is generally easy 

 to obtain a sufi[iciently approximated value for the mean temperature on the days 

 for which it is required. 





Observed 



Covr'n to 



Corrected 





Observed 



Corr'n to 



Corrected 





tempera- 



average 



tempera- 





tempera- 



average 



tempera- 





ture. 



month. 



ture. 





ture. 



month. 



ture. 



January .... 



20M0 



°.00 



20°.10 



July .... 



67''.44 



—".04 



67°.40 



February 



22.93 



+.22 



23.15 



August .... 



65.60 



—.10 



65.50 



March .... 



31.64 



+.45 



31.99 



September 



58.28 



—.11 



58.17 



April .... 



42.56 



+.57 



43.13 



October .... 



47.78 



—.20 



47.58 



May .... 



52.69 



+ .27 



52.96 



November 



36.71 



—.15 



36.56 



June .... 



62.29 



+.37 



62.66 



December 



24.86 



—.11 



24.75 



The corrections found for Brunswick appear to conform to average values, in 

 quantity and sign, to what we might expect in our latitudes. 



Using the monthly means in the last column we form the equation : — 



T = + 440.50 + 230.15 sin ( e + 2480 45') + 0°.88 sin (29 + 2580 00') 

 + 0.T9 sin {SO + 225 )+ 0.11 sm (49 + 333 ) 



with a probable error of a single monthly representation of +0°.17. The angle 

 6 counts from January first at the rate of 30° a month (or 59'. 2 a day). The 

 numerical quantities in (T) indicate a normal character of the annual fluctuation. 



Comparison of Obseeved and Computed Temperatures. 





Observed. 



Computed. 



Difference 





Observed. 



Computed. 



Difference 



January . 



February 



March 



April 



May 



June 





20M0 

 23.15 

 31.99 

 43.13 

 52.96 

 62.66 



19°.92 

 23.19 

 32.15 

 42.88 

 53.27 

 62.40 



+°.18 

 —.04 

 -.16- 

 +.25 

 —.31 

 +.26 



July .... 



August .... 



September 



October .... 



November 



December 



67°.40 

 65.50 

 58.17 

 47.58 

 36.56 

 24.75 



67°.52 

 65.55 

 57.93 

 47.92 

 36.19 

 25.08 



— °.12 

 —.05 

 +.24 

 —.34 

 + .37 

 —.33 



' The reader may be referred to an interesting paper on this subject, by De Forrest, in the May 

 number of Silliman's Journal for 1866. See also his improved results in the September number of 

 the same journal. If we have to deal with single years, either common or leap, the correction to 

 refer the results to an average year and average month may be taken from the following table giving 

 the number of days and fractions to be added or subtracted from each calendar month. The signi- 

 fication of the signs will be readily understood by examining that of January in connection with the 

 rule given in the text. 





For common years. 



For leap years. 





For common years. 



For leap years. 



January . 



. — .56 



— .56 days. 



July 



. +1.06 



+ .06 days 



February 



. +1.87 



+ .87 



August . 



. + .50 



— .50 



March 



. +1.31 



+ .31 



September 



. + .94 



— .06 



April 



. +1.75 



+ .75 



October . 



. + .38 



— .62 



May 



. +1.18 



+ .18 



November 



. + .81 



— .19 



June 



. +1.62 



+ .62 



December 



. + .25 



— .75 



It is, however, hardly worth while to apply corrections to results by a single year, the mean values 

 from four years even are yet quite irregular. The numbers given in my reduction of Dr. 1. 1. Hayes' 

 Arctic temperatures refer to the calendar year. 



