X marks the spot, but there are few around the house, unless you own a game of jacks or collect old dolls, the homemade kind, with cross-stitches for eyes. You can find X as well on labels glued to jars of poison stored under the sink and in the garden shed, the letter made of femurs and placed below a skull. X’s Phoenician ancestor, samekh, means fish. Even to this day, there’s something fishy about X. You remember it drawn on the blackboard in school, the teacher saying, “X is the unknown.” You couldn’t stop thinking it could be chalked across everything outside the self—the cat, the red-eared turtle in the pond, clouds and sumac, a good night’s sleep, yeast blooming in sugar water in a measuring cup. The last entry in Webster’s under X is xyster. You’d be suspicious if you found it with the can opener, whisk, meat thermometer and garlic crusher in your drawer of kitchen gadgets. Used in surgery, and from the Greek, it’s an instrument for scraping bones.