James B.Gamelin, age 10, of west Warwick, R.I., for his question:

Do we use more natural or synthetic rubber?

This wide awake question caught your old reporter napping. HE took it for granted that the world still usea more natural rubber. Then he began checking the facts and hunting for items to make the rubber story interesting and, oh my, old Andy had to change his first idea in a very big way.

The competition between natural and synthetic rubber began in the 1930s: Chemists wanted to create a man made substance that would be as useful and perhaps cheaper than natural rubber. A quarter of a century ago they were producing about one per cent of all the rubber WE needed and this synthetic rubber was very costly:

Nowadays, roughly seven tenths of all the rubber used in America is man made. And most of the world's rubber goods are synthetics. The story of this scientific triumph is a dramatic page of our history. Rubber is processed from a substance ca11ed latex that is flexiblc and bendable, stretchable and bounceable. Natural rubber is processed from the liquid, latex rich sap of the very fussy rubber tree. It grows only in a warm, wet climate and only in deep, super rich soil.

In the past, we depended on Malaysia and Indonesia to supply most of our crude rubber. Then came World War II. The Japanese took over these areas and cut off nine tenths of our raw supplies. The loss, however, was overcome promptly by typically American reaction on the home front. The government and manufacturers, chemists and businessmen all put their heads together and shared their know how to produce good, inexpensive synthetic rubber.

They did the job in jig time and in 1945, America produced 1,120,000 tons of man made rubber almost as good as natural rubber. In 1955, the government got out of the rubber business and sold its Equipment to private manufacturers. The large companies now have chemists and more chemists who work constantly to improve the quality and develop new recipes for better and still better synthetic rubbers. America now uses about 2,500,000 tons of synthetic and about 550,000 tons of natural rubber each year.

Synthetic rubbers are plastics made mostly from raw materials taken from coal and petroleum. The standard variety is called S13R and it performs as well. Or better than natural rubber. Many other varieties are made to do special jobs in which natural rubber fails.

A tough and springy foam mattress may be made of a synthetic called polyurethane. Polysulphite rubber makes hard and durable rollers for printing presses. A synthetic called bunan is rubbery cloth and leathex products. Certain heavy duty airplane parts are made of silicone rubber that will withstand extremes of heat and cold and never become brittle.