180 



RECORD AND RESULTS OF 



of 30.5 days for common and leap years respectively. New monthly snms and 

 means Avere then taken. 



In the formula' 



T=A + Bi sin (0 + Ci) + B^ sin (23 + G,) + B, sin (39 + Q + . . . . . 

 T represents the temperature for any part (month or day) of the year, and the angle 

 counts from January 1st (0'' A. M.) at the rate of 30° a month or 59'. 2 and 59'.0 

 a day for common and leap years. 



For Port Foulke we have : — 

 I'=+6°.06 + 33°.ll sin (0 + 242° 14') +6°.32 sm (29 + 119' 3') +0°.74 sm (30 + 318°) 



For comparison, the expression for Van Rensselaer Harbor was found : — 

 T=— 2°.2O + 35°.59sm(0 + 251°43')+6°.72sm(20 + 69°47')+3°.2Osm(30+lT°) 



And for Port Kennedy : — 

 r = + 2^02+39°.20 sin (0 + 249° 05') +0".80 sin (29 + 256° 56') + r.06 sin (30 + 275°) 



The observed and computed mean monthly temperatures compare as follows ; the 

 months are of equal length, and it will be seen that the temperatures of the actual 

 months differ but little from those of the normal months. 















Port Foulke, 1860-61. 



Normal month. 



Observed 



Computed 



Difference 





temperature. 



temperature. 



0.— C. 



January ...... 



—250.91 



-22°. 94 



—30.03 



February . 













—24.63 



—21.90 



+ 3.21 



March 













—22.41 



—22.19 



+ 0.38 



April 













—9. 95 



—5.25 



—4.10 



May . 













+ 24.81 



+ 18.98 



+ 5.83 



June. 













+ 34.52 



+ 31.43 



—2.91 



July . 













+ 40.53 



+ 41.56 



—1.03 



August 













(+36.01) 



+ 33.88 



+ 2.19 



September 













+ 22.50 



+ 22.21 



+ 0.23 



October . 













+ 1.46 



+ 10.81 



—3.41 



November . 













4-2.96 



—0.12 



+ 3.68 



December . 













—13.18 



—12.61 ~ 



—0.51 



Seasons and year. 









Spring 



—2.52 



—3.02 



+ 0.50 



Summer 



( + 31.04) 



+ 31.62 



—0.58 



Autumn 



+ 10.91 



+ 10.81 



+ 0.16 



Winter 



—21.26 



—21.11 



—0.09 



Year 



+ 6.06 



+ 6.06 



0.00 



month (and consequently cast over 0.58 of it to February) ; include with February, March 1, and 

 0.83 of the second; with March, April 1 and 0.25 of the second ; with April, May 1 and 0.61 of the 

 second ; with May, June 1 and 0.08 of the second ; with June, July 1 and 0.50 of the second ; with 

 July 0.92 of August 1 ; with August 0.33 of September 1 ; with September 0.15 of October 1 ; with' 

 October 0.11 of November 1 ; with November 0.58 of December 1. For leap years : Retain only 

 0.5 of January 31, casting the other half into February; with February include March 1; with 

 March 0.5 of April 1 ; with April May 1 ; with May 0.5 of June 1 ; witli June July 1 ; with July 

 0.5 of August 1 (leaving the other half to be counted in with August); with September include 0.5 

 of October 1 ; and with November 0.5 of December 1, 



^ For a further development of these functions to suit various numbers of observations in a cycle, 

 see U. S. Coast Survey Report for 1862, Appendi:f No, 22, 



