TIII: OKIUT OF URANUS. 107 



In the last column we have the seconds of concluded correction for clock and 

 instrument to be applied to the ob>< rv.il time of transit of Uranus. 



1690, December '23. Right Ascension. 



Star. Time of Tr. K. A. of star. Clock. C'. R. Der. C". 



)'. m. H. h. DI. i. h. m. I. m. t. I. i. t. 



a Arietis, 7 48 40 1 49 52.1 5 58 47.9 58 29.3 1.1 1.2 31.6 



7i Arietis, 8 30 : I 2 32 8.4 5 58 45.6 58 33.9 0.7 +1.7 32.9 



a Arietis, S ;J:J 17 2 34 31.0 5 58 46.0 58 34.7 0.7 +2.9 32.5 



* Arietis, 8 40 21 2 41 38.0 5 58 43.0 ,58 33.0 0.6 0.2 33.8 



f> Arietis, 8 ,r> 44 2 54 3.0 5 58 41.0 58 33.0 0.5 +0.5 33.0 



r Tauri, 9 27 47 :5 29 13.6 5 58 33.4 58 31.1 0.1 1.3 32.5 

 Uranus, 9 41 49 



A Tauri, 9 45 3 3 46 31.1 -5 58 31.9 58 32.4 0.0 0.8 33.2 

 a Virginis, 19 415 13 8 58.2 5 55 16.8 56 49.3 

 a Bootis, 19 58 31 ^ 14 1 34.0 6 56 57.5 58 39.0 



Hourly rate of clock, 0'.6 



Deviation of instrument for each degree of Z. D., 0.5 



Transit of Uranus, 9 41 49.0 



Correction for clock and instrument (mean), 5 58 32.8 



Observed R. A. of the planet, 3 43 16.2 



1690, December 23. Declination. 



Z. D. observed. Refraction. Declination. Eq. point 



a Arietis, 29 29' 10* +0' 33" 21 58' 53" 51 28' 36* 



n Arietis, 35 18 55 + 41 16 9 4 51 28 40 



<r Arietis, 37 41 +0 44 13 46 58 51 28 42 



e Arietis, 31 23 15 +0 35 20 4 37 51 28 27 



S Arietis, 32 55 55 +0 37 18 31 40 51 28 12 



i Tauri, 28 20 55 +0 31 23 6 53 51 28 19 

 Uranus, 31 52 35 +0 36 



A Tauri, 30 15 55 +0 34 21 12 3 51 28 32 



Circle reading for Uranus, corrected for refraction, 31 53' 11" 



Equatorial point on circle, 51 28 30 



Declination of Uranus, from observation, + 19 35 19 



1712, April 2. Right Ascension. 



The discordance of clock errors, and the time which intervened between the 

 transit of the planet and that of the first star, seem to render an accurate reduction 

 impossible. _ 



