86 TEMPERATURE CORRECTIONS. 



The second and third columns give the hours at which the highest and lowest mean temperatures 

 occurred. The fourth column shows the equivalent of the temperature range in the first column, in 

 terms of the correction to V; for comparison with this, the fifth column gives the range of the 

 corrected V diurnal inequality. To illustrate the table, take the case of December, 1902. The Vertical- 

 Force magnet had its highest temperature at 3 p.m., its lowest at 4 a.m., the difference between the two 

 being 4 16 C. The correction to the apparent value of V necessary to eliminate the effects of temperature 

 was greater at 3 p.m. than at 4 a.m. to the extent of 145y, or about 2-8 times the total range obtained 

 for V after applying the correction. 



In the Midwinter months the temperature range was small, and the hours of highest and lowest 

 temperature varied much from month to month. Thus, the V-inequality results for the Midwinter months, 

 and especially that for the whole season, should be but little influenced by temperature uncertainties. 

 Subsequent to March, 1903, the regular diurnal variations of temperature in the Magnetic Hut were small. 

 It is thus satisfactory that the inequalities finally deduced from the 1902 and 1903 curves agree in type. 



