Glass & Mirror Interesting Facts
Is that really silver on the back of a mirror? Is that why it's called silvering?
While at one time silver was used, today mirrors are made by depositing a thin layer of aluminum, called the tain, to the back of a piece of glass. The back of the mirror is then painted or coated to seal the metal from corrosion.
How will a mirror complement my home decor?
Mirrors help to create the illusion of space, thus helping to make small spaces seem bigger. For example, if your room is long and narror, placing a mirror on one of the longer walls will help to make the space seem wider. A good rule of thumb is to place the top of the mirror at a height halfway between the top of your head and eye level. That's the point on the mirror a ray of light from the top of your head reflects off on its way to entering your eye. Similarly, the bottom of the mirror should be at a height equal to half the distance between your eyes and the floor.
Is it true that glass flows, and that's why old windows are thicker on the bottom?
We can safely say that no, glass does not flow. Old windows that are thicker on the bottom are the result of two explanations. The first is that when glassblowers made the glass, the process they used spun the glass to create a round, mostly flat and even plate which was then cut to fit the window. Therefore, it was basic centrifugal force, used in the spinning, that made the ends thicker. Second, when the windows were installed, the thicker ends were placed on the bottom to create a more stable structure. Over time, this gives old glass the appearance that it has "flowed" downwards over time.
Did You Know...?
According to ancient Roman historian Pliny the Elder, the Phoenicians first "made" glass in 5000 BC. After landing their nitrum-laden ships in present-day Syria, they prepared their meals on the beach. While cooking they used the nitrum to prop up their pots, and the fire's intense heat melted the nitrum, mixing with the sand and creating rivers of opaque "glass."
The earliest known examples of man-made glass are beads made by the Mesopotamians dating back to 2,500 BC, although glass was used by the Phoenicians as a pottery glaze as early as 3000 BC.
Glass is neither a solid or a liquid; instead it is generally treated as an amorphous solid. This is because glass has no melting point; there is no temperature where it melts -- it simply becomes more viscous as the temperature rises.