1, Colored glass is placed into the opening of the glant glass furnace. The furnace burns at over 2000 degrees farenheit. The furnace is not flat and level . Instead it has al slight slope to it so the glass flows down to the lower end as it contlnues to melt. The lower end sits above the marble-making machine which is inside of the building.
2,The melted glass exits the furnace through a special ceramic spout that is shaped like a funnel. The flow of the glass stream is controlled by a metal gate.
3, The stream of molten glass flows into the shearing device which cuts the glass stream into smaller pieces called gobs. The gobs of glass silde down chutes and fall onto the forming screws of the marble making machine.
4, The forming rolls of the marble-making machine are grooved like long sets of screws. The molten gob of glass rides in the groove and becomes rounded.As it travels alone the screw, the marble is constantly rotating in different directions. Think of rolling a plece of clay between your paims. Same idea. The longer the marble is rolled , the more perfectly round it becomes. it also becomes less hot alont the way.