[4] Measurements as early as 1855 only gave a rough approximation of the line or were done piecemeal, and a fuller survey was done for private purposes and not shared publicly.

[5] The survey which would eventually establish the longitudinal California–Nevada border was conducted by Alexey W. Von Schmidt working under General Land Office Commissioner Willis Drummond starting in 1872.

He observed Professor George Davidson of the U.S. Coast Survey using telegraph to coordinate time signals and get a location of the 120th meridian.

Von Schmidt accepted these measurements and headed to lay out the route north to Oregon,[5] placing markers of stones, wood, and iron at regular intervals; the only one to do so thoroughly.

[5] The Houghton-Ives line had been accepted as the border, despite being poorly mapped and landmarked, along the 120th meridian until 1977 when California brought suit to Nevada in the United States Supreme Court to establish the true boundary.

Google maps shows that the Verdi California–Nevada boundary marker is approximately 525 feet (160 m) west of 120 degrees longitude.