nickel brick
n.— «When you talk about changing attitudes toward people of different colors, or different ethnic groups, one of the things that impressed me most as I reflect back was an activity held at the annual St. Columbkille’s picnic at Rogers Park. A big canvas drop was set up, let’s say 8 feet wide and 10 feet high, and in that drop about four feet off the ground was a hole, and a black man would stick his head out through that hole. Now, about 25 to 30 feet away, you’d be standing and you’d be given these, as they were called “nickel bricks,” a type of baseball, and you’d throw it at the head of the black man to see if you could hit him.» —“Remembering Old Allston-Brighton: Schools and racial, ethnic relationships” by Bill Marchione Allston/Brighton TAB (Needham, Massachusetts) Ju;y 4, 2008. (source: Double-Tongued Dictionary)