Gail Atherton, age 10, of south portland, Me., for her question:

What do they use to make sealing wax?

This wonderful gummy material was one of the very first plastics. It becomes soft and moldable when warmed, and solid and very hard when cool. In the past there was no strip of gum on the flap of an envelope. The letter writer took a :tick of sealing wax and warmed the end in a candle flame. He put a soft gob of the wax on the envelope, pressed it down and waited for it to dry.

In olden times, beeswax was used to make sealing wax. Later, fine sealing waxes were made from plant resins mixed with turpentine. Modern sealing wax contains no wax at all. The best kinds are made from shellac and venice turpentine and usually colored with bright red dye. .