>>9431160No.2. Wilhelm then positioned the dumpy level 4m from the left measuring pole and adjusted the height of the theodolite so that it was level with the zero mark made previously when the dumpy level was located in the middle of the two poles. The dumpy level was then turned 180° and the cross hairs on the theolite were used to find its position on the right measuring pole 996m away. This was 12 to 14cm higher than the zero mark in the control.
