Context: Mass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets were cut into smaller window panes with nonuniform thickness, typically with the location of the pour centered in one of the panes (known as "bull's-eyes") for decorative effect. Modern glass intended for windows is produced as float glass and is very uniform in thickness.

Question: What were the areas at the center of an old sheet of glass called?
Answer: bull's-eyes

Question: In early 20th century glass production, the glass was thickest at what part of the sheet?
Answer: the center

Question: Currently window glass is made as what?
Answer: float glass

Question: How was the bull's-eye used?
Answer: for decorative effect

Question: What were the areas at the center of window panes called?
Answer: Unanswerable

Question: In early 20th century glass production, the glass was poured at what part of the sheet?
Answer: Unanswerable

Question: Currently large sheets are made as what?
Answer: Unanswerable

Question: How was the table used?
Answer: Unanswerable

Question: What was poured onto a large window pane?
Answer: Unanswerable