New Mexico Statutes Chapter 4. Counties § 4-14-1. Original county boundaries

All that part of the county of Socorro situated to the eastward of a direct line drawn from north to south, from Malpais, and to be the western line of the new county, is hereby constituted and established, a new county which shall have the name of, and be called the county of Lincoln; the line of the north of said county shall be the dividing line of the county of Valencia; from thence drawing a line eastward without interfering with the boundaries of the county of San Miguel; and on the south a line passing east and west through the head of El Ojo de Tularosa; and this shall be the fixed boundary between the counties of Dona Ana and Lincoln.