370 REPORT— 1872. 



Augmenting factor. 

 Aj, Bj •002S 



Aj.B^ -0115 



AjjB, '0262 



Ae,B(. -1107 



As, B^ -2092 



to take account of the circumstauce that the mean height for each honr has 

 heen taken virtually for the height at the middle of the hour, we find cor- 

 rected values for the coefficients (A, B), from which we have the following 

 amplitudes and epochs, according to notation of § 3 : — 



25. The hour-angles of the ideal stars having heen assumed to be each 

 equal to zero at the commencement of the observations, the previously 

 found epochs (e^, e^, &c.) have to be corrected for this assumption in order 

 that the tide-components may be referred to the true positions of the ideal 

 stars. The correction to be added to the epoch of the diurnal tides will be 

 equal to the true hour-angle of the ideal star at the commencement of the 

 observations. In the semidiurnal the correction will be equal to twice the 

 hour-angle, for the terdiurual'^ three times, and so on. The longitudes of 

 the sun and moon and of the lunar perigee used in getting the true hour- 

 angles will necessarily be their mean longitudes. In addition to the above 

 six series, others have since been analyzed and included in the schedule. 

 The amplitudes and the corrected epochs of the whole are as follow : — 



Yr. 1864. Ao = io-i988ft. Average inclination ofmoon's orbit to earth's equator (I) = 2o°-3. 

 S M L N MS 2SM SMS 



(7—n) (r-"^) (r-4ff-iw)(y~i(7 + i'ar)(y-i(T-i),)(y + <T-2),)(y-|(7+i»/) 



