We had several painted Skelly squares in our Cypress Hills projects back in East New York Brooklyn. Skelly, Boxball, HopSkotch, seemed every ten feet. I remember generations of us playing it back in the sixties, and waiting our turn to. It was always the older teens first, then they’d leave to go the the basketball courts, or the top circle. Then we’d get the chance. My favorite cap of use was the coke top or wine cap with wax, but like many, I longed for the cool glass ring of the Coke, Tab, Fresca, or beer bottle ring. Seems I remember the older teens (back in the sixties) used to fish them out of the trash cans, and proceed to skim the necks on the asphalt or stoop until you got the perfect ring.