Calculation of Occultations, 1 65 



Example, 



P. L. par in alt. 5593 P. L. H. M. 8296 



Log sec 23° 49' .0387 Log sec 5° 36' .002 1 



P. L. 45' 26" 5980 P. L. corr. H. M. 



P. L. 1« 



Log cosec 23° 50' 3935 



P. L. 20' 4" 9528 



3504 

 P. L. 22' 14" 9083 



P. L. diff. decl. 41' 58" 6324 p ^ ^gM 49s 

 Log sec 56° 28' 2577 ' 1053 is 



5579 



P. L. 23' 11" ^ 10 3 29 MiddU. 

 Log cosec 56° 28' .0791 



P. L. 34' 59" 7115 

 45' 25" 34' 59" 

 23 11 20 4 



22 14 14 55 Nearest distance. 



iv. It may be necessary, in some cases, to repeat the calcu- 

 lation of the effect of parallax at the time thus found, in order 

 that the true visible motion during the interval may be em- 

 ployed, instead of the hourly motion, and the calculations of 

 the two last precepts may be repeated with the correction of the 

 visible orbit thus obtained ; or the whole computation may be 

 verified by any of the common methods. The nearest distance, 

 compared with the moon's apparent diameter corrected for the 

 altitude, readily gives the length of the star's path behind the 

 moon, and the visible hourly motion the corresponding time.- 



Exam-pie. Supposing 14' 5b" the correct distance, the moon*g 

 semidiameter being 15' 16" at noon, and diminishing 9" in 

 24 hours, it will be 15' 12" at 10", and the augmentation for 

 altitude 21° being 6", we have 15' 18" for the corrected semi- 

 diameter. 



