From the U.S. Department of the Interior Bureau of Land Management module on ‘Original Surveys’: The Interior Department appropriation Act of 1911 (June 25, 1910, 36 Stat. 703, 740) initiated the “direct system” of public land surveying.
‘Primarily iron post and steel construction’
‘Surveys are typically accurate and consistent’
‘Processes established under the direct system, eliminated incentives that encouraged fraud and corruption‘