New Mexico Statutes Chapter 4. Counties § 4-1-2. Change in south boundary

All that portion of the county of Bernalillo situated south of a line commencing at a point on the east bank of the Rio Grande where the southern foot of the Loma de Isleta strikes the Rio Grande, and running thence to the Canon del Infierno, and then following the old line of both counties to the east, shall be cut off from the county of Bernalillo, and included within the county of Valencia. All the above-described land shall be annexed to and form part of precinct number fifteen of the county of Valencia.