Feature 3: The Southwest Convento Wing

Just prior to the end of the Fall 1995 field season, excavations shifted to a series of units forming a trench line intended to determine the location of the original sandstone foundations of the southwest convento wing. Because local historians had indicated by way of personal communications that the original foundations, if they had existed at all, would have been destroyed long ago with the grading of the 2nd Street road bed immediately adjacent the area of the original mission quadrangle. In December of 1995, an east-west datum line was set and the site subdivided into a grid of 2x2 meter units. Subsequent to the setting of the east-west datum line, crew members Ken Halla and Keith Iida were directed to initiate excavations at Units 20s12w, 20s16w, and 20s18w, respectively. On the first day of excavation in Unit 20s16w, in Trench 1 of Feature 3 (which consists of Units 20s10w through 20s18w), initial excavations resulted in the exposure of the top of the sandstone foundation wall of the southwest convento wing. Because it was unclear at that time whether or not the wall foundation in question was that of the interior or the exterior wall of the southwest convento wing, excavations were shifted to the area of Units 20s12w and 20s10w.

After several frustrating weeks attempting to locate the interior foundation wall of the Southwest Convento Wing, subsequent work conducted during the Spring 1996 field season resulted in the recovery of the foundation section at a depth of over 55 centimeters. As a result of the discovery of the interior foundation wall, it was finally determined that the original wall section recovered in Unit 20s16w and 20s18w was in fact the original outer wall of the mission quadrangle. As such, the first definitive evidence that the foundations of the southwest convento wing were both intact, and lay within the present perimeter of the mission courtyard area, was determined once and for all. While the top of the outer wall foundation recovered from within Units 20s16w and 20s18w was recovered at a depth of little more than 10 centimeters below the surface of Unit 20s16w, the top of the inner wall foundation in Units 20s10w and 20s12w lay at a depth of over 55 centimeters below the surface of said units. This interior wall was found to measure no more than 90 centimeters in width, and to have been mined for stone at some time after the collapse of the original walls of the southwest convento wing. The mining, reuse, and recycling of the sandstone blocks and cobbles from the original foundation walls was apparently an ancient practice at the Old Mission of San Juan Bautista (e.g. Farris 1991). Because the interior wall of the Southwest Convento Wing is relatively crude by comparison with that of the outer wall of the same structure, questions remain as to the original structural integrity of the buildings that constituted the architecture in question. Other significant findings from the excavation of Trench 1, Feature 3, center primarily on the architectural history of the original adobe room blocks of the mission quadrangle, as well as that culture history discerned here in preliminary fashion from those indications sifted from the facts at hand.

As for the interpretation of the architectural history discerned from the archaeological exploration of the former Southwest Convento Wing room block, it has been determined that a devastating fire took down that section of the Southwest Convento exposed as the result of excavations undertaken within the areas of Trench 1 (Feature 3) and within the area of the old Torreon at Feature 4, and Unit 22s0e. In each and every one of these areas, a five to ten centimeter layer of ash and charcoal was found to underlie all existing roof fall through which excavations were conducted by this project. At several points within Trench 1, including Units 20s10w through 20s18w, this same ash layer was noted from sidewall exposures. In each and every area of the quadrangle that has been exposed to date, a significant body of evidence has been recovered that indicates that fire gutted a significant portion of the roofing timbers of the southwest convento wing. The layer of ash and charcoal in question also contained many hand-forged colonial era nails that provide indications that the nails were not salvaged as a result of the fire that destroyed the buildings in question. Because much of that ash and charcoal layer was found to have been deflated, and subsequently spread throughout the area in question, it appears likely that after the fire destroyed the Southwest Convento Wing, the area remained abandoned and largely undisturbed for a period of years. In addition to the recovery of forged nails from within the ash layer, significant quantities of burnt sandstone, adobe, and roof tiles were encountered. The roughly 30 to 40 centimeter thick layer of roofing tiles encountered above the ash layer that interfaces with the original clay floor was in turn overlain by a five to ten centimeter thick layer of sterile soils. The thin layer of sterile soil is in turn overlain by a thick layer of midden containing deposits ranging in age from the 1830's through 1890's. That area interfacing with the surface in turn contained deposits of mixed provenience and age. That body of material culture recovered from the area of Trench 1, Feature 3, ranges from Spanish colonial majolica wares (both local and imported) recovered from the clay floor area within the convento room block at Unit 20s14w (and from within the roof-tile layer noted) to English, French, Chinese, Mexican, Japanese, and Philippine ceramics and porcelains (Deagan 1987; Godden 1964; May 1972; Mendoza and Torres 1994; Weigle 1983; Williams 1978).

Given the cultural and natural deposits in question, preliminary interpretations center on a culture-historical and architectural reconstruction that indicates that the Southwest Convento Wing of the mission quadrangle was brought down in a fire that occured during the course of the 1830's, or that era coinciding with the period of Mexican secularization at the mission and within the community of San Juan Bautista (Clough 1996; Farris 1991). A tentative reconstruction of the events underlying the abandonment of the Southwest Convento Wing would suggest that after the structure was destroyed by fire, a period of some ten to twenty years passed during which little to no cultural activity was associated with the area of the ruined southwest convento wing. Ultimately, in the period after about 1850 or 1860, early American and related European trade items begam to appear among the cultural materials and debris associated with the trash midden that came to overlay the thin layer of sterile soils that formed over the old ruins of the Southwest Convento Wing in the period before about 1860. These and related materials from that area of the site suggest that the melted-adobe walls of the room blocks contained within the Southwest Convento Wing had come to serve as receptacles for the dumping of trash associated with the early American era, and that this activity continued through the late 19th century Victorian period of San Juan Bautista's history.