Conservation lab at the Texas State Library and Archives Commission. Casey Dunn Professional Photography.
The Texas State Library and Archives Commission undertakes conservation efforts to preserve original records in our collections and to make them useable for research. Conservation activities include examination, documentation, treatment, and preventive care. This exhibit highlights work performed by the conservator of the Commission’s Summerlee Foundation Conservation Laboratory.
TSLAC has undertaken a multi-year project to conserve its Confederate muster rolls. Prior to 1970, these muster rolls, which contain basic information about enlisted men in the Confederate Army, received conservation treatment known as silking. A thin piece of silk gauze was glued to the document with a water-based paste to hold together brittle, torn pieces. This technique is no longer used as it has been determined that the silk makes paper more acidic, turning it brown and brittle. Modern conservators often use Japanese tissue in place of silk.
Each month, approximately 15 sheets of muster rolls are treated to remove their silk lining, mend tears, guard against acidity and allow easier handling. These documents’ fragile condition previously made them unavailable to researchers. After treatment, the muster rolls can be handled safely by researchers.
Confederate muster roll with silk before treatment.
Confederate muster roll with silk removed after treatment.
Humidification is a process that involves placing paper in an enclosed chamber with water vapor. This process prepares the paper for washing by gradually increasing its water content, reducing stress on paper fibers and ink. Humidification also softens the paste that holds the silk in place.
Paper is enclosed in a chamber with water vapor to increase its water content and prepare it for washing.
Washing, De-silking, and De-acidification
Paper is submerged in a shallow bath of de-ionized water (water that has been filtered of ions and other harmful impurities). After several minutes, the silk is gently removed from both sides of the paper, and the document is gently brushed to remove residual paste.
The document is transferred to a second bath for de-acidification (a process that neutralizes the harmful acid content of paper and protects against future degradation).. Afterwards, the document undergoes controlled drying, first in the open air, and then between absorbent blotter sheets.
Silk is removed from the paper in a shallow bath of de-ionized water.
The cracks and tears previously held together by the silk must be mended with a new material. Repairs consist of thin, flexible Japanese tissue strips attached with wheat starch paste. Applied correctly, these mends are strong, nearly invisible and can be removed in the future should a better mending technique be developed.
A thin strip of Japanese tissue is applied to a tear.
Last, the mended documents are fitted with a clear sleeve made of a stable archival plastic known as Melinex or Mylar. The sleeve is easily removed, and its open sides allow the paper to release any acidic byproducts it may produce in the future.
After conservation, the fragile muster rolls are ready once again for researchers to use.
A muster roll is fitted with a custom sleeve for improved handling and storage.