478 



OPPOSITION OF MARS, 1849-50, 



Coincidence of wires to be applied ; and as the zero wire was not disturbed throughout, but the telescope moved in declination to bisect the star, 

 the coincidence applies to all. 



30.0038 30.0081 



Mean = 30.006 rev. 1 rev. = 26" .06925. 



After tenth measure, position circle verniers turned 180. Screw-hend now below. Tlie cross eliminates the coincidence of the wires by taking 

 the mean of screw above and screw below. 



