Francis A. J. Ianni, in his book "Black Mafia: Ethnic Succession in Organized Crime" writes: "By 1925 there were thirty black policy banks in Harlem, several of them large enough to collect bets in an area of twenty city blocks and across three or four avenues." By 1931, big time numbers operators in Harlem included James Warner, Stephanie St. Clair ("Madame Queen"), Casper Holstein, Ellsworth "Bumpy" Johnson, Wilfred Brunder, Jose Miro, Joseph Ison, Masjoe Ison and Simeon Francis. The game survived despite periodic police crackdowns.