Figure 5-10. - Philadelphia rod marking.
inch. The indicated reading of the target can be read either by the rodman or the instrumentman. In figure 5-12, you can see that the 0 on the vernier scale is in exact alignment with the 4-foot mark. If the position of the 0 on the target is not in exact alignment with a line on the rod, go up the vernier scale on the target to the line that is in exact alignment with the hundredths line on the rod, and the number located will be the reading in thousandths.
Figure 5-11. - Direct reading of 5.76 ft on Philadelphia rod.
Figure 5-12. - Target.
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