What is this asking ???
A surveyor compares the bearings at two ends of a lineunderground by using a gyrotheodolite. The results at each end canbe compared after they are corrected for grid convergence, meridianconvergence, deflection of the vertical and index error in theinstrument. Could the effects of deflection of the vertical beignored in practice? (Look up some values of the deflection of thevertical in extreme cases, and estimate how much they affectdirections).
