In the latter half of the eighteenth century frontier conditions in northern
                         New Spain had deteriorated to such an extent as a result of Indian
                         depredations, management of presidios etc., that the Spanish crown found it
                         necessary to order an examination of the entire frontier with the view of
                         relocating presidios and making whatever other adjustments might be
                         necessary to prevent further abandonment of the frontier settlements. The
                         Marques de Rubi was given the assignment of investigating this problem.
                         He began his investigation in 1766. Royal engineers Nicolas de La Fora
                         and Joseph de Urrutia assisted Rubi by drawing plans of presidios and
                         drafting maps of the area traversed.

                         As a result of the Rubi recommendations, a new line of defense was
                         established, uniform fortification plans were prescribed, and numerous
                         changes were made in regulations governing military personnel. The new
                         line of fortifications was to be composed of some fifteen presidios situated
                         at about 40 league (or 120 mile) intervals extending from the Gulf of
                         California on the west to the Gulf of Mexico on the east along what is now
                         approximately the northern boundary of Mexico. The order implementing
                         the realignment of the Presidios of the Frontier Line was published in
                         1772: REGLAMENTO e instrucción para los presidios que se han de
                         formar EN LA LINEA DE FRONTERA de la Nueva España.

                         Hugo O'Conor was named to the post of Commander-Inspector of the
                         military forces of the frontier provinces and took over the command on 17
                         February 1772. Between 1773 and 1775, O'Conor succeeded in relocating
                         12 presidios that had to be moved and added two others. Detachments of
                         troops were ordered to be stationed at San Antiono de Bejar and Arroyo
                         del Cibolo in Texas. These however were not considered to be Presidios of
                         the Frontier Line. (pp 7-8, Spanish Presidios of the Late Eighteenth
                         Century in Northern New Spain, Rex E. Gerald, Museum of New Mexico
                         Research Records No. 7, Santa Fe, 1968).

                         Presidios of the Frontier Line (from west to east):

                         Santa Gertrudis del Altar, founded 1755 with 30 soldiers from the presidio
                         of Sinaloa. Presidio was designed to restrain the Seris, Pimas and Papagos.

                         Tubac, founded 1753 following the Pima uprising of 1751. The garrison was
                         moved to Tucson in 1777.

                         Terrenate, founded 1742 southwest of Huachuca mountains Sonora. Late in
                         1775 Santa Cruz de Terrenate was relocated near what is now Fairbank
                         Arizona. Apache Indian attacks forced relocation of the of the presidio
                         again in 1780 to a site near the arroyo of Las Nutrias.

                         Fronteras, originally founded in 1692. It was located for a while to the north
                         in the San Berardino Valley, possibly in Arizona. Later in 1780 it was
                         moved south by Teodoro de Croix.

                         Janos, founded 1690.

                         San Buenaventura, founded in 1776 by troops from Guajoquilla.

                         El Paso del Norte, founded as a result of the Revolt of 1680 in upper New
                         Mexico. Spaniards moved downriver (southward) and founded presidio at
                         the site of present Juarez, Chihuahua. Presidio was constructed in 1683. In
                         1773, because the town of El Paso was well populated and could defend
                         itself, the presidio was moved southward to Carrizal.

                         Guajoquilla, erected in 1752 on orders from the Viceroy Revilla Gigedo.
                         Later known as San Eleazario.

                         Julimes, located in 1777 at the former site of the presidio of La Junta at
                         the confluence of the Conchos and Del Norte (Rio Grande) rivers.

                         Cerro Gordo, founded after 1772 as part of the new frontier defense.

                         San Saba, San Saba-Aguaverde was founded in the new presidial line after
                         1772.

                         Santa Rosa del Sacrament, now Ciudad Melcho Muzquiz, Coahuila. It was
                         moved north after 1772.

                         Monclova, founded in 1674. The villa or town of Monclova was the capital
                         of Coahuila in 1780. At that time the presidio was located to the east
                         nearer the Rio Grande.

                         San Juan Bautista, found in 1699.

                         La Bahia del Espiritu Santo, founded in 1772 as the last and easternmost
                         presidio of the line. The original site was where Fort St. Louis stood on
                         Matagorda Bay. It was moved in 1726 to the Guadalupe River and later
                         removed to the north bank of the San Antonio River at the site of the
                         present town of Goliad, Texas.

                         San Antonio de Bejar, founded May 5, 1718 was not considered a presidio
                         of the line, but it was defended by a detachment according to the
                         regulations of 1772.

                         Arroyo del Cibolo, founded in 1771 as a detachment site. Presidio was
                         deactivated in 1782 at orders of Teodoro de Croix, (pp.94,95, Lancers for
                         the King, Brinckerhoff amd Faulk, Phoenix, 1965).