300 R - CHAELES CHREE: SOME PHENOMENA OF 



TABLE XVI. Co-ordinates of Diurnal Inequality Force Vector. 



horizontal plane. The p, (j> curve in the horizontal plane is that usually termed the 

 " vector diagram." 



If AN, AE (or AW), and AV denote departures of the northerly, easterly, and 

 vertical components of force from their mean values, 



<f> = tan" 1 (AE/AN), = tan" 1 (p/AV), 



p = V /(AN 2 + AE 2 ) = AN/cos <f> = AE/sin <f>, 

 K = p/sin 6 = AV/cos 0. 



24. The three headings q, d, and d q in Table XVI. denote respectively results 

 derived from quiet days, results derived from the 209 disturbed days, and results 

 derived from the difference inequalities, which are obtained by subtracting quiet day 

 from disturbed day hourly values. If the causes operative on quiet days continue to 

 exert the same influence on disturbed days, then the results in the d-q columns 

 represent the disturbance element pure and simple. The calculations were carried at 

 least one decimal place further than appears in the table. 



A drawing of the p, <f> curve on quiet days will be found in (A) (fig. 11, p. 377). 

 In this case there is no retrograde motion, <f> continually increasing throughout the 



