An apparatus and methods of refining glass, in a multi-stage, downwardly cascading manner, include a melting chamber housing molten glass and having an outlet, a first refining chamber downstream from the melting chamber and having a first outlet and a first inlet below the outlet of the melting chamber, and a second refining chamber downstream from the first refining chamber and having a second outlet and a second inlet below the first outlet of the first refining chamber. The first refining chamber has a first negative pressure and the second refining chamber has a second negative pressure.

An apparatus and methods of refining glass, in a multi-stage, downwardly cascading manner, include a melting chamber housing molten glass and having an outlet, a first refining chamber downstream from the melting chamber and having a first outlet and a first inlet below the outlet of the melting chamber, and a second refining chamber downstream from the first refining chamber and having a second outlet and a second inlet below the first outlet of the first refining chamber. The first refining chamber has a first negative pressure and the second refining chamber has a second negative pressure.

An apparatus and methods of refining glass, in a multi-stage, downwardly cascading manner, include a melting chamber housing molten glass and having an outlet, a first refining chamber downstream from the melting chamber and having a first outlet and a first inlet below the outlet of the melting chamber, and a second refining chamber downstream from the first refining chamber and having a second outlet and a second inlet below the first outlet of the first refining chamber. The first refining chamber has a first negative pressure and the second refining chamber has a second negative pressure.

An apparatus and methods of refining glass, in a multi-stage, downwardly cascading manner, include a melting chamber housing molten glass and having an outlet, a first refining chamber downstream from the melting chamber and having a first outlet and a first inlet below the outlet of the melting chamber, and a second refining chamber downstream from the first refining chamber and having a second outlet and a second inlet below the first outlet of the first refining chamber. The first refining chamber has a first negative pressure and the second refining chamber has a second negative pressure.