Sweat Test for Cystic Fibrosis

What to call this battery box, wires dangling:
Electrodes? A polygraph. A torture device.
The usual white linoleum in this small room
Hot as a summer attic and on a metal table,
The box that my daughter Amani names Pirate,
Saying it looks like a face with an eye patch.

The nurse doesn’t name it. She explains,
“The sweat sample’s collected by using liquid
On a patch of skin.” She touches my daughter’s
Forearm. “Painless. Tingles with a weak electrical
Current.” She attaches the electrodes.

Serena, my younger daughter, spins
Around and around, chanting, “Dizzy. Dizzy.”
The machine hums like an electric razor.
I brush Amani’s hair from her damp forehead.
Stroking her hair, my fingers do their usual work,
Finding tangles and gently working strands free.

How rarely I notice myself breathing or
Holding my breath. Last night I was thinking
About the soul, its papery home.
Walking in the house I know so well
I can navigate in the dark, I thought:
All that I love most moves nearby.
One child snoring. The other quiet as a pillow.
I freeze in her doorway. Wait. Then see
Her chest rise, a small wave.