That was how to make egg coffee. Which might seem like an odd skill to have in this day of super-incredible-fancy-dancy-do-everything-but-make-dinner coffee makers, but it will come in extremely handy when we're camping. And it also appeals to my sense of history and self-sufficiency, since my dad learned it from his Aunt Hattie (who our daughter is named after), an incredibly skilled and talented woman.
1. Step 1, 2. Step 2, 3. Step 3, 4. Final Product
The egg apparently traps the grounds so the coffee can brew. Aunt Hattie used to make coffee like this on her mother's wood stove in a house with no electricity, so it was only a short jump to making it the same way on a campfire.
Follow the links above for a detailed tutorial on how I did it. While it's not rocket science, my first attempt didn't go perfectly. Hopefully others will learn from my mistake.
Anyway, if you find yourself sitting at a campsite dying for a cup of coffee, you might want to try it. It's fun and the coffee's great.
And it beats the heck out of the brown water you get from coffee in a tea bag.