lime, plaster; Use of Lime in Colonial New Mexico; Documentary Evidence for Lime Kilns in El Paso
An Essay by Rick Hendricks, PhD
Background
One of the earliest recorded uses of whitewash or plaster in New Mexico dates from 1583. In Diego Pérez de Luján's account of the Antonio de Espejo expedition, there are several mentions of interior whitewash in the Piro pueblos south of present-day Socorro, New Mexico. It seems likely, however, that this was not lime plaster, but gypsum, or even a wash of white clay. The indigenous peoples of central Mexico had the technology for producing lime plaster before the Aztecs; it was found to have been used at Teotihuacán, but I know of no indications that the Pueblos utilized lime plaster or lime mortar before the arrival of the Spaniards.
Quicklime is obtained by calcining chalk or limestone, that is, heating it to a high temperature to drive off volatile material, a process that is completed when the carbonic anhydride is driven off and the oxide retained. The quicklime was traditionally prepared sufficiently in advance of its application so that it could cure. When added to water, quicklime forms calcium hydrate, which is then applied as plaster. When dried, the plaster is hard and water resistant. Sand is added to produce lime mortar.
A number of pre-1680 Pueblo Revolt sites in New Mexico show archeological evidence of the use of lime plaster, as well as gypsum plaster. According to James E. Ivey, the pattern of using lime plaster on building exteriors and, as a minimum, gypsum plaster on interiors and frequently lime plasters on interior too, was fairly well established in colonial New Mexico. Such a pattern of plastering is likely at the Salinas Basin pueblos, which were abandoned before the 1680 Revolt. Recent excavations at San Marcos, which was abandoned after the revolt, have uncovered a lime plaster floor, as well as wall plastering. One of the churches at Pecos Pueblo is known to have had a lime plaster exterior.
There was another less well-known use for lime in colonial New Mexico. Lime was traditionally used in the preparation of nixtamal, which was corn boiled in lime water from which masa is made for making tamales and tortillas. Unground nixtamal is used for making posole.
El Paso Lime Kilns
The evidence for the use of lime plaster on El Paso area churches is mixed. An archeological field school conducted by the University of Texas at El Paso in 1984 on one of the possible sites of one of the several constructions of the Socorro mission recovered considerable plaster. Apparently no testing was done on the plaster, but it is at least suggestive that plastering was done on church buildings. On the other hand, a document dating from 1816 lamented the embarrassing fact that the church of our Lady of Guadalupe in El Paso was in a poor state of repair and not even whitewashed.
The best evidence for the use of kilns to make lime plaster come from a public works project in eighteenth-century El Paso. At the time of his official inspection of the El Paso area in 1751, New Mexico governor Tomás Vélez Cachupín, in consultation with the leading citizens, ordered the construction of a dam and a new headgate for the acequia madre. He specified that the construction material was to be cal y canto, or stone masonry, that is, stone with lime mortar. While it is not unheard of for this term to be applied to simple stone construction, it is more commonly used to denote stone and lime mortar. In documents regarding eighteenth-century Texas missions, cal y canto is used to differentiate a superior construction material in distinction to piedra y lodo, rock and mud.
All growers of grapevines in El Paso were be taxed at the rate of four reales for every one hundred units of grapevine stock. A real reluctance to pay for construction of the dam, which the growers blamed on poor harvests resulting from insect pests, flooding, drought, and hail led to delays until 1762. In that year, Governor Vélez Cachupín, who was back in office for a second term, again ordered the construction the hydrological projects. The leaders of El Paso decided to apply the bequest of a rich former resident, one thousand pesos to be applied to a public work, to the project. By this time, the viceroy, the auditor of war, and the king's legal advisor had all approved the project.
Trouble began when an architect declared that the dam could not be constructed owing to the sandy bottom of the river. The master mason approved by the citizens of El Paso, Santa Fe presidial soldier Juan de Alarid, was pronounced unfit for the job by Governor Vélez Cachupín who stated that Alarid was no architect and had no experience with so large a project. There were few masons in the El Paso area who worked in cal y canto and no masters. Then it was decided to remake the headgate and extend and reinforce the acequia madre in cal y canto. In October 1762, Celedonio de Escorza, who was in charge of the construction project, notified the alcalde mayor and captain of the El Paso presidio, Manual Antonio San Juan, that the citizenry was ready with their carretas and tools to begin construction on the kilns to be used to burn the limestone. He asked that the Indians from the Guadalupe mission provide labor, requesting that San Juan see fit to order their governor, Antonio Zarcillo, to tell them to join with the Spaniards in the project, which was mutually beneficial. The Indians were to transport limestone and help in the construction of the kilns.
Preparation of the lime got underway, but the construction of the waterworks stalled. When Alarid was rejected, the governor suggested contracting a suitable person in Chihuahua. The only master builder in Chihuahua with the needed experience, José Sagandia, was busy working on another dam project. Besides, the salary on offer did not interest him anyway. Heavy spring rains augured a bad flood season that was rapidly approaching. Fearful that the projects would not be finished in time, the citizens opted to reinforce the dam, headgate, and acequia madre with dirt as they had always done. And so the great cal y canto dam project was unceremoniously dropped.