J. D. Everett on Reducing Observations of Temperature. 23 
March are reckoned part of February, giving February 38 days, 
and leaving January and March only 29 days each. 
2d. When the last 8 days of February are reckoned part of 
March, so that January will have 81 days, February 26, an 
March 34 
3d. When the last day of January and first of March are 
reckoned part of February, so that January will have 30 days, 
February 31, and March 30. 
4th. When calendar months are adopted, giving January 31 
days, February 29, and March 81. 
he resulting values of A, A, and E, are as under. 
Days. Days. Days. Ao Ay E, 
Jan. 29, Feb. 33, March 29, gives 46°91 10°87 88° 37’ 
Oe RS RRS OO: oe 10°81 83° 19’ 
#80, FEEL, OS egg ES ESOS 10°78 88°. 33" 
BLE MB, OS RacBIy ss eet 10°78 83° 217’ 
Here a difference of 7 days in the length of February causes a 
difference of ‘03 in the mean temperature, ‘06 in amplitude, and 
18', or about $ of a day, in date. From the last two lines it 
appears that the difference between giving February 29, and 31, 
ays does not affect either mean temperature or amplitude, to 
i places of decimals, and only affects date by about 75 of a 
Tshall not attempt to show in detail the advantages which 
meteorology may be expected to derive from the extensive 
application of the method of reduction here pro 
Tecognized in every branch of statistical enquiry, et no such 
measure is usually applied to “date of phase,” and the measures 
to retard the air temperature, but Iam not aware that different 
p ae 
The laws which connect date of phase with extent of range 
also offer an interesting field of investigation. — Generally speek 
ing, the causes which retard the former diminish the latter. 
