It is only on the earth's axis that such an observation is possible.
"My Attainment of the Pole"
Frederick A. Cook
When during two turns around the clock dial, the shadows are all of about equal length, the position of the earth's axis is positively reached-even if all other observations fail.
"My Attainment of the Pole"
Frederick A. Cook
Nevertheless his opinions will not alter the axis of the earth.
"The Maid of Maiden Lane"
Amelia E. Barr