Plss Standard Lines

In the survey of the principal meridian and other standards lines (base lines, standard parallels, and guide meridians), two independent sets of measurements are made, but only the mean of the two measurements is shown in the final field notes. (BLM 1973, paragraph 3-9.) "A principal meridian is intended to conform to the true meridian, extending north or south or both directions, from the initial point as conditions require." (BLM 1973, paragraph 3-8.) "The base line is extended east and west from the initial point on a true parallel of latitude." (BLM 1973, paragraph 3-10.) "Standard parallels, which in earlier years were also called correction lines, are extended east and west from the principal meridian, at intervals of 24 miles north and south of the base line, in a manner prescribed for the survey of the base line." (BLM 1973, paragraph 3-12.) Guide meridians are extended north from the base line or standard parallels at intervals of 24 miles east and west from the principal meridian, in the manner prescribed for running the principal meridian and terminate at the point of their intersection with the standard parallels. (BLM 1973, paragraph 3-14.)