588 SCIENTIFIC RESULTS OF ZIEGLER POLAR EXPEDITION 



The Establishment of the Port may be derived from the mean lunitidal interval as follows : 

 Establishment of Port = H WI + Table 24* for phase age before spring tides (5) 



Cape Flora Teplitz Bay 

 d h d h 



The phase age (see (34)) is . . . 2 5.6 2 2.4 (6) 



Ratio Ratio 



The value of S, ^ M, is 0.333 0-409 (7) 



in m 



With these values Table 24* gives . +25.6 +29.4 (8) 



and substituting these values in (5) gives 



ni h m 



Establishment of Port for Cape Flora = HWI + 25.6 = 10 10. i (9) 



Establishment of Port for Teplitz Bay = HWI + 29.4 = 6 43.0 (10) 



The mean lunitidal intervals may also be obtained from the harmonic constants by the 

 equations : 



Mean high-water lunitidal interval = HWI = 0.0345 (M°, — v) ( 1 1 ) 



Mean low-water lunitidal interval = LWI = 0.0345 (M", — ze/) + 6.21A (12) 



Where v and w are such that 



2M, sin (2M°, - M° J + sM^ sin (3M°, - M°„) +. 



tan v = 



tanze' = 



I'Mj + i^yi, cos (2M°, - M°J H- 3'MeCos (sM", - M°,) + 

 2M^sin (2M°, - M°J - 3M,sin (3M°, - M°e) + 



- i^'M, + 2'''M, cos (2M°, - M° J - 3'Me cos (3M°, — M^) -}- . . 



From (11) and (12) we obtain : 



Cape Flora 



h m 



HWI 9 40.9 



LWI 3 29.7 



A comparison of these values with those of (3) and (4) indicates a fairly satisfactory 

 agreement, especially if we take into account the great difference in the methods used to obtain 

 the two sets of results. 



The sun's efEect upon the time of the tide is to disturb the mean time of its occurrence, 

 making it alternately earlier and later, according to the moon's phase. 



The priming of the tide is the periodic acceleration of its time of occurrence, due to the 

 sun's efEect. At such times the lunitidal intervals are less than their mean, so that the tides 

 occur earlier than the average. The priming of the tides occurs during the period between 

 new or full moon and the following quadrature, beginning and ending at a time equal to the 

 age of the phase inequality after these phases. It attains its maximum effect soon after the 

 first and fifth octants of the moon's phase. 



The lagging of the tides is the corresponding retardation in the time of its occurrence, the 

 greatest effect being soon after the third and seventh octants of the moon's phase. 



* Whenever any table is referred to here by number, unless otherwise stated, it is contained in Appendix 7, 

 United States Coast and Geodetic Survey Report for 1894, for tables up to 35, and in Appendix 9, Report for 

 1897 of the same Survey, for tables having numbers greater than 35. 



