Question

Why glass go downwards and thick at bottom after some time
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Answer 1

Answer:

It is well known that panes of stained glass in old European churches are thicker at the bottom because glass is a slow-moving liquid that flows downward over centuries. ... The arrangement of atoms and molecules in glass is indistinguishable from that of a liquid.

Answer 2

Explanation:

Glasses in the windows of old buildings are found to be thicker at the bottom because of the manufacturing process of glass used at that time. ... This glass was then cut into desired size and shape. Thicker edge of the glass was kept at the bottom of windows attain more stability of the windows.