■54 



A VOYAGE TO 



'778- were made only as an experimenr, without aiming at much 



, ^ 'y nicety. 1 alfo meafured moflly one way -, whereas I ought 



to have brought alternately the reflected and direft images 

 to contrary fides, with refpe^t to each other ; reading the 

 numbers off the quadrant, in one cafe, to the left of the be- 

 ginning of the divifions; and, in the other cafe, to the right 

 hand of the fame. It is evident, that half the fum of thefe 

 two numbers mud be the true meafurement, independent of 

 the error of the quadrant ; and this is the method that I would 

 recommend. 



But I am well aflured, that it might have been obfervcd 

 much nearer; and that this method may be ufeful when 

 neither the beginning nor end of an eclipfe can be obferved, 

 which may often happen. 



Inamediatcly after the eclipfe was over, we obferved the 

 diftance of each limb of the moon from Pollux and Arietis ; 

 the one being to the Eaft, and the other to the Weft. An op- 

 portunity to obferve, under all thefe circumrtances, feldom 

 happens ; but when it does, it ouglu not to be omitted ; as, 

 in this cafe, the local errors to which thele obfervations are 

 liable, deftroy each other ; which, in all other cafes, would 

 require the obfervations of a whole moon. The following 

 arc the refults of thefe obfervations : 



^. r-ic ., ^Arktis ~ 204' 22' 07" ? „ , „ 



Myfclfwiih ) o -o' ^/^mean 2^421' 5' 



^ / Pollux - 204 20 4 i 



. , {yjrictis - 20+° 27' 4c" ? o ^1 ,, 



Mr. King With J „ ., \ ^ ^^„ ^mean 204° 18' 29" 



^ I Pollux - 204 9 12 3 ^ 



Mean of the two means _ _ _ - 204° 19' 47 

 The time-keeper, at 4'' 30', to which time all 

 the lunar obfervations are reduced 



204' 04' 45" 



The 



