The table must be accurately oriented once the table is shifted otherwise the lines drawn from the new stations will not correspond with the previous ones.
The alidade should be properly centered on the station point on paper.
Papers often get contracted or expanded so it is best to use paper clips.
The table should be accurately centered with a plumb bob and fork.
The rays should be drawn using a straight ruler only.
It is better to check the distances manually from time to time for better efficiency.
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