Fort Mifflin Cell Door

Philadelphia, PA



A Fort Mifflin staff member was crossing the lawn when they sank into a patch of soft earth. Smartly realizing they may have made an important discovery, museum staff immediately turned to Materials Conservation for help. Working with Archaeologists excavating the site, our team provided conservation services for the site including wooden doors with cryptic historic handwriting etched into their surfaces.

We implemented a phased conservation program. Phase One: monitoring interior temperature and humidity ranges. Several wooden doors inscribed by prisoners were unusually well preserved, but fragile from prolonged environmental exposure. In order to prevent further damage to the excavated artifacts, we carefully transported each element back to our lab and into a humidified chamber where we replicated the casemate environment. Over eight months, we lowered the humidity within the tented lab to slowly bring the pieces to an equilibrium. This treatment provided gradual environmental change without creating structural stresses to the doors and related architectural elements. Once stabilized, all the items were safely returned and are now on permanent public display.

Sukari Keetin