What is the purpose of the milled slot in Frank Lloyd Wright's windows?

Frank Slot frank slot In Frank's case, the payout occurs after every 15th pull of the slot machine, making it a fixed ratio schedule 2 **Example**: Imagine Frank franks farm slot free play Jonte were playing Frank's Farm and won $ mill The potential on this online slot is huge

frankie dettoris magic seven slot Sold for $688 Height 72 inches Slot machine does not come with a key The figure is carved wood The machine is apparently unsigned; images of the slot