Washing, washing, and more washing

“How are things going with the project?”  “What have you guys been up to?”  These are questions that I get asked a lot.  The answer is:  washing.

The last coffin was internally excavated on January 2, 2018 meaning that since then, all the skeletal material is now a collection of bones in boxes.  Before any analysis can be done, all those bones have to be cleaned.  Why?  So we can really “see” all the features and marks on the bones that help us determine things like sex, age at death, trauma, and other signs of health, nutritional state, disease, and injury.  Dirt left on the bones can obscure such features.

Washing a skeleton is a lengthy task that can be very tedious.  The tools required are a toothbrush, a tub of tap water, a wooden skewer (for up-close work), and a good playlist of ‘tunes.  Bones that are well preserved can be “wet brushed” meaning that the tooth brush is dunked in the tub of water.  “Dry brushing” is just that – a dry toothbrush to brush away the dirt.  This is used on bones that are deteriorated or could otherwise be damaged by contact with moisture.  Bones should never be submerged in water.  That can cause the outer layer of bone (cortical bone) to split and flake off as the bone dries.

Every skeletal element gets cleaned of dirt.  Certain areas like the ends of ribs, the pubic symphysis (where the two halves of the pelvis meet), and fragile areas like the eye orbits require a delicate hand.  Adults have 206 bones and children have more depending on their stage of development.  It can easily take a full 8-hour day to clean a single skeleton.  With 496 individuals recovered from the First Baptist Church of Philadelphia’s cemetery, that’s two full years of workplace washing for a single person.  Fortunately we have a small army of cleaning volunteers; but even so, this phase of the project will take a while!