Thursday, June 2, 2011

Dirty Laundry

From the desk of Colleen Wilson,
Conservator at the Royal BC Museum

Many of the textiles returning to Helmcken House after the installation of the new fire suppression system were very dirty.  To clean or not to clean?  Both the original appearance and the loss of evidence must be considered.  Vacuuming away dust that has settled on exhibits is one thing; washing away the fingerprints of use is another.  Could the grease stains on a pillowcase be from Dr. Helmcken’s hair oil?  Might the stains on a jelly bag reveal something about 19th century fruit processing?  The lives of 150 years ago differ from ours in the details and it is amazing how much is not recorded about the minutiae of “everyday life”.  The information held in tea cosies and carpet slippers can be invaluable.

Not everything was created with laundry in mind, and years of use have enfeebled many aged textiles.  Composite artifacts may not withstand treatment more strenuous than vacuuming because the parts may respond differently creating destructive internal stresses: if the lace inserts shrink in water, the dresser scarf could self-destruct.  Many dyes developed in the 19th century are not stable in water; some can be stalled by controlling the pH of the rinse water, but only if experimentation has established a safe procedure beforehand.  All fibres must be assessed, all colours, including those of patches and darns must be tested before wet treatment. 
Making the decision to wash textiles at the RBCM is made easier by the quality of water in Victoria.  Because it does not contain the minerals that make water “hard”, and requires only minimal filtering to remove particulates, delicate artifacts can be safely and effectively washed in tap water.  Positively charged calcium and magnesium ions can lock negatively charged soil to negatively charged fibres; conservators faced with hard water must use de-ionised or distilled water to prevent the formation of intractable “re-deposited soil”.
Old textiles can easily be damaged while wet.  To make the risk worthwhile, detergent should provide maximum cleaning but minimum stress.  In the past, laundering meant lots of heat and soap – very effective at getting things clean, but too harsh and alkaline for fragile artifacts.  Contemporary detergents, even those recommended for delicate fabrics, contain perfume and dyes to conform to our current ideas of how “fresh” and “clean” should look and smell (few of us would choose brown detergent!).   While additives cycle through our household laundry they can pose problems for artifacts that are rarely re-washed.  The traces of dye and perfume, not to mention “fabric conditioners” and “optical brighteners” can change colour or interact with older materials unexpectedly, as well as presenting a 21st century version of “clean”.   

The attraction of an historic house is seeing artifacts in the context of their original settings, not isolated in protective cases.   Artifacts displayed in the open, though, are vulnerable to many dangers including soil and pollution; just the removal of dust can be very stressful for aged materials.  The rooms of the past, however, would not have been filled with a century of dirt.  While cleaning artifacts takes its toll, displaying soiled ones gives a less than historically accurate impression.
Dirt has sifted through the knitted bedspread on open display.
Soiled and stained textile being considered for washing.
The unstable red and green dyes have bled into the white wool of a child's embroidered coat. 

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