Claire Waltons age 12, of West Vancouver, B.C.
How do they make different colored neon lights?
Strictly speaking only the red ones are neon lights. We call them all neon lights because neon was used to make the first of them. Such a good idea was bound to be improved. Different substances„ plain or blended make those beautiful signs on Main street glow with different colors.
A neon bulb is an almost‑vacuum glass tube, Most of the air is taken out and a little neon put back in. Neon is a gas, It is present in very small traces in the air. The neon tube is connected with an electric current. Nothing happens until the current is turned on, All you have is a clear tube containing little invisible gas,
The electricity from the current passes through the tube when you turn on the switch. It agitates the bitsy gas particles. This makes them joggle about bump into each other and heat up to a red glow: The neon sign shines with a red light. A neon light is bright enough to be seen through mist and fog, You can see the SODA sign on the drug store blazing away at high noon. No ordinary electric light can compete with the sun in this way.
Some of the signs on Main street are a clear, soft blue color. These should really be called mercury signs. For the gas used in these tubes is mercury vapor, otherwise they are like neon tubes.
Some signs glimmer with a radiant golden glow. The gas used in these tubes is helium, the light‑weight gas used to lift dirigibles, In a tube of clear glass, helium does not radiate a very powerful glow. For this reason, the glass tube is usually tinted amber. You can usually tell a yellow light sign even when the current is turned off.
Green light signs are often brilliant enough to compete with blazing red neon. This color, like the golden yellow, is a combination. The glass tube is yellowish or amber tinted. The gas inside is mercury vapor, the one that glows in a clear tube to give us the delicate blue signs. When the electric current is on the blue gas and the yellow gas blend to give us those beautiful green signs, then the switch is off you see only the yellow tinted tube. You must tinted tubes you must wait for the current to set the gas joggling to find out whether the sign is to be green or yellow.
Some signs glow with a brilliant white light. This is brought about by a careful mixture of gases in the tube: The different colors cancel each other out and blend to make white light.
Fluorescent tubes gleam with a hard strong light. The gas inside is usually mercury vapor. The tube, however, is. especially tinted on the inside with fluorescent paint, When the light is switched off, this tube is opaque with a yellowish cast to it, The tiny particles of fluorescent paint add their own sparkle t‑o the ,light, ‑ When the gas particles begin to glow, they simmer and glimmer along with them.