A symbol-bearing receptacle for a fluid, said receptacle comprising a container for said fluid and a symbol disposed on said container, said symbol having a water reactivity characteristic that differs from the water reactivity of said container. The module can include a sampling subsystem having: a sample loop; an absorbent trap; or a gas chromatography injection port. For idle gaming machines, the attraction game is hidden from the player and the owner of the gaming machine may invest a fixed amount of money so that the player receives all money wagered plus the invested amount. When the check disk member is closed, the diverter member engages the actuator member to allow a first fluid to flow through the first upper aperture or to allow a second fluid to flow through the second upper aperture.