Irt 



— I". Ito. \'\)v Ihc niciiu nidiiis llic \iiliic h' =: U'A'2" J)>^ \N'as lakcK, 

 which is Ihe value adojilcd \)\ NKWcdMit in his hisl '^i'oai work 

 OM the motion ol' the mooii, as it seemed lo me tiiat ilio. radius lo 

 lie used in oci'idlatioiis mnst he the same as the mean radins of 

 the \-er\' sharp prolile ol' the moon whieh pi'ojects its(>||' on the 

 hrif^lit disc of' tiie snii. 



1 

 In the compnlalion ol the parallax I have assumed tor tiie 



-JDS. -J 



elli|itieity of the earth, hoth for the calenlation of the reduction to 

 geocentrie latilnde and of the radius-vector of the earth at the place 

 of obser\atioii, and for dc<luciii;j, tiie constant of the sine-parallax. 

 1 therefore assumed for the constant .3422".47 (Nkwcomb, Astr. Pap. 

 IX J p. 44) and a eoi'rection of -j- ()".40 was applied to the N. A. 

 value. The observations were made in the position of the instrument : 

 ('lamp-West and Circle A. was read; for the reduction of the declination 

 so found to the mean of the two circles and the four positions of 

 the inslrnment (objective anil ocular-end can be interchanged and tiie 

 instrument can be reversed) accortliuu to llu' investigations made in 

 the observatory a correction of -\- ()":H mnst be applied to the 

 decliiuition. Moreover for the reduction lo Aiwkks's system a correc- 

 liou of — ()".!() has to Ik^ applied, for that to Nkwcomu's system 

 one of - ()".04. 



The observations and their reduction are !;iven in the following 

 table : the first column indicates whether oi' not a reversing prism 

 was used ; the second column (dutains the hour-angle, at which the 

 observatiiui was made ; the third the mean of the foin- microscopes 

 for the moon; Ihe fourth the same for the nadir; Ihe liftli the sum 

 of the corrections for division-errors, run, reiiuction to the meridian, 

 llexure of the inslrunieut. irregularities of the limb, distance, incli- 

 nation and cnrvalurc of Ihe vvires. the si.xth the correction for refrac- 

 tion ; ihe seventh ihe /.erjilh-dislance obtained in that manner and 

 the eighth the geocentric declination of the centie of the moon. 



Jinb 



Nadir 



Corr. 



Refr. 



Zenith-dist. 

 limb 



Declination 

 centre 



witlioiit pr. 

 with pr. 

 without pr. 



-74s! 140° 17'5T"28 0^7'41"55i — S"()2 47"15 39°50'39"45 



+14 

 491 



17' 21 "48 



17' 14"5n 



-f4"42 47" 16 

 — 9"80 47"17 



51 2"82 

 51 24"n3 



-|-13°12'35"52 

 12' 12" 45 

 11'51"51 



r>v reducing the first and Ihe third declination to tlie moment of 

 th<' second one we linallv obtain: ,1 = -\- i:]° IT IT'M 



12.45 

 Ji.öO 



