A stabilization record is a structural history of a site or an architectural unit of that site: a room, a wall or a doorway. It is intended to provide full information on the original condition of the unit, including any inherent structural weaknesses, previous protective or preservation measures and, in detail, the techniques and materials employed to bring the unit to its present state of preservation. It is advantageous to record the various steps of unusual or difficult solutions, of new or experimental techniques and special features of the site or project. The amount of detail that will be required will vary with the size and complexity of the individual project, ranging from the brief description necessary for a wall fragment uncovered in grading operations, to the full reporting required to document the realignment of walls and the installation of integral members.
The preparation of comprehensive stabilization records is time-consuming. It may require a good deal of research into the past history of the structure. One example is the comprehensive stabilization of Talus Unit, excavated and partly stabilized by the Museum of New Mexico, and on which there are the excavator's notes but no publication. Sufficient time must be scheduled to permit the search for and inclusion of pertinent data in the individual room records. Stub walls and partition walls are often removed by the excavator to facilitate the search for or clearing of lower structures, and it is important to know the extent and former location of these in planning the preservation of any area. It is also of particular value to know the location of loosely backfilled areas, for these often hide evidence of undercutting and weakness, and pose problems in surface drainage.
In addition, stabilization records in conjunction with cost accounts are of inestimable value in developing budgets for future programs.
The permanent record sheets designed for the Southwestern National Monuments about 1937, and still in use at the Ruins Stabilization Unit, are self-explanatory (see examples, figs. 62-64). With a few minor changes in headings, which can be made on the job, they can be used for a wide variety of work. They can be attached to a clip board or binder, and most of the entries can be made in the field. Accumulative data can be entered from a daily log at the completion of each unit. The presentation of data can be somewhat modified in practice, depending on the kind of site and amount of work required. There are two pages to each stabilization record, a "first sheet" for references, justification, orientation and architectural background. Where a series of small adjacent rooms or similar units have the same references, justification, orientation and the same architectural background, only one "first sheet" need be filled in to include a group of contiguous rooms. A separate "second sheet" will be used to detail the condition of the ruin prior to the start of work, and the previous and current repairs.
The individual record sheets should be followed by pages showing at least one "before" and one "after" picture. Extensive photographic coverage is desirable and may include general overall views showing the conditions of adjacent terrain which may affect the site, as well as detailed shots of specific techniques. Where a portion of a structure is to be reset or will have to be replaced, as in setting integral members, it is a decided advantage to take the photographs well in advance of the actual work. Enlarged prints can then be used as guides in resetting masonry, to obtain authentic contours of wall tops, and for filling in small details. If the work is large, and there are many small details, the addition of vertical and horizontal scales in the photograph will insure accurate dimensioning.
The maximum size print that can be used to show both a "before" and "after" on the same page is 4 by 5 inches. In special cases it will be convenient to have general overall pictures in 8x10's mounted on a single page. A good photographer, using 35 mm. film and making careful enlargements, can produce excellent 4x5 prints at a considerable savings in cost. However, most supervisory personnel will not always have good darkroom facilities at their disposal and, unless custom finishing is available, commercial 4x5 enlargements are not apt to be as satisfactory as those made from larger negatives. The 4x5 press camera and contact prints are the most useful and result in the greatest savings in time.
Materials and Processes
The following are random observations based on the somewhat over 15,000 negatives now on file at the Ruins Stabilization Unit.
In smaller communities, check local services before entrusting them with film for development. Most photofinishers use DK-20, a long-lived developer that is fair for some film, but totally unsuited for materials in the Eastman Royal Pan family. Negatives are apt to be too thin for use. The most satisfactory system has been to develop negatives in the field. This permits an immediate quality check, and the photographs can be re-taken if necessary.
Daylight tanks holding a dozen sheets of film, prepared chemicals, and washing aids or hypo eliminators reduce the work involved. The use of a hardener in warm weather, and a wetting agent before drying, aid in the production of good quality negatives. With the use of a hypo eliminator, archival quality negatives and prints with long-range keeping qualities can be made. However, this service is not always obtainable from commercial establishments.
The film used will depend primarily on personal preference and familiarity with the characteristics of a particular brand or kind. In general, extremely high speed types are to be avoided and the best results are had with medium speed film with fairly good contrast. The use of filters with panchromatic films is often a decided advantage. On the other hand, some of the most satisfactory photographs in the files of the Ruins Stabilization Unit are the results of attempting to duplicate old glass plate pictures taken by Jackson and Mindeleff. These were taken with an old view camera using Eastman Commercial film with a slow orthochromatic emulsion. Skies were lost, but the rendition of surface texture and detail in masonry is excellent.
Photographic coverage of a site takes time and should be started far enough in advance so that advantage can be taken of the correct position of the sun for good lighting. In the Southwest, one of the major defects of contact prints are areas of deep shadow in which all detail is lost. These shadows can be somewhat compensated for in developing, but it is far better to take the picture when the lighting is optimum for the area to be shown. If it is impossible to do this with natural sunlight and reflectors, it is well to remember that flash bulbs for fill-in lighting produce more contrast which more closely approximates sunlight than the electronic speedlights. Supplementary lighting is good for close-ups of details and at moderate distances, but it requires more experience and often extensive equipment for use in large areas. Some of the best architectural record shots are made on overcast days with negatives developed to a fairly high contrast. A vexing problem, which is rarely solved by additional lighting, is that of making one specific part of a structure stand out in a photograph without having it confused with extraneous background material that cannot be kept out of the picture. An experienced photographer with a relatively long lens can usually throw the background out of focus. A large, lightweight piece of canvas can be held as a background cloth to isolate specific walls or sections; the improvement in clarity is worthwhile.
The only satisfactory method of mounting prints for the record pages is thermosetting mounting tissue. While a press is an advantage, small quantities can be pressed with an ordinary household iron that has settings for different fabrics. One way to avoid the use of mounting tissue, and the resulting extra bulk, is to print the photographs two to a page on ad-type paper. At the time the Southwest Regional Office of the National Park Service was operating a photo lab, all the Ruins Stabilization Unit's records were printed on this paper, which will accept typewriter impressions, and most of them were excellent. Very high commercial costs and the reluctance of most photofinishers to attempt printing two negatives of differing densities on a single contact sheet have prevented the continuing use of ad-type paper.
Stabilization forms and photographic pages such as those depicted in figures 62-64 should be used regularly for all archeological stabilization work and for historic structures whenever possible. These can be supplemented, particularly in historic buildings, by additional means of recording. Entering repairs or other changes on Historic American Building Survey (HABS) records, or comparable measured drawings (where available) is a particularly convenient means of supplementary recording. An accurate ground plan is a necessity for an archeological site of any size. While not approaching the detail of HABS sheets, ground plans can be used to show type and location of work accomplished. While successive jobs on a building over a period of years will be shown in different reports, large ground plans are an effective medium for recording and presenting the cumulative total of preservation measures.
Recording maintenance work poses a number of problems. Minor maintenance such as cleaning drains and the resetting of small areas of masonry dislodged by visitor traffic does not require entries to stabilization records if the work does not change the structural history of the unit. However, such work should be recorded when a change is made in materials or in location of accessory items such as drains. For example, a good deal of capping in the Southwest 30 years ago was accomplished with soil-bitumen mortar. It has become necessary to replace some of this within the last few years, particularly on low walls close to self-guided trails. When stones in this capping are set in tinted concrete mortar, it constitutes a change in materials and, though the same stone is used and the appearance of the unit has not been altered, the substitution of concrete for soil-bitumen should be recorded.
In such instances, unless the maintenance is very extensive, it is not necessary to make a new, two-sheet stabilization record. This is time consuming and results in excessive duplication. For ordinary maintenance of any site, one new "first sheet" can be used to cover the entire site. The principal entry will note that this is maintenance work and that the detailed entries can be found in the comprehensive record. Give the year and page number of this comprehensive record. Then it will only be necessary to enter the maintenance work on the "second sheet." Ordinarily, stabilization records for each site are bound in permanent volumes, by years. Since maintenance records are seldom very extensive, this results in some rather thin-bound volumes, but this system has proven more effective than attempting to add additional data to the larger comprehensive records. If there are a few sites in an area, and two or more receive maintenance in the same year, such records can be bound together.
Some form of a daily log or field notes should be kept, not only to record progress, but to keep an accurate record of man-days and materials expended. While for many smaller projects the required data for the record can be entered directly on the sheets in the field, some additional record will be required from which to take the amounts of materials used. An engineer's field book is convenient to carry and easy to use if the tendency to crowd small pages is avoided. Separate columns can be used for materials and calculation of man-days expended.
If one unit, such as a single wall or room, is being stabilized at a time, it is a simple matter to arrive at the total materials used. However, several small units will probably run concurrently, and materials such as concrete mortar, soil-cement, etc., will be distributed from a central point. In such cases, the work expenditures can be measured at the end of each day and the materials prorated among the separate jobs. If a little effort is spent at the beginning to determine just how much cement or bitumen or other material is required for a definite unit of work (a square foot of capping or a cubic foot of wall repair, etc.,) and this is checked from time to time, the total materials used can be more easily prorated among the various individual projects.
While the individual record sheets have entries for individual architectural unit-costsman-days and materials per room or areait is more realistic to keep total project costs. This permits the inclusion of truck and equipment costs, supervision, and other overhead charges that can not be accurately prorated among many small units. At any rate, whether or not individual room expenses are kept, some record should be made of total project costs. These can then be broken down into the most convenient units for future estimates. Breaking this back down into the cost per room is one method of obtaining quick estimates. Another method is to work out costs per unit-of-work, so much per lineal foot of capping on walls 12 feet high or over, so much for lower walls, the cost of patching a square foot of masonry, or the cost of grading and draining a square yard of room interior. This unit-of-work method provides slightly more accurate results, although it does take more time to work up and more time to apply.
Last Updated: 16-Apr-2007