Bruce Stevenson, age 13, of Decatur, Ill., for his question:

WHO INVENTED LINOLEUM?

A man named Frederick Walton invented linoleum in England about 1860 when he found that linseed oil, when exposed to the air, became a rubber like material that could be used as a floor covering.

Linseed oil comes from the flax plant. Walton called his new product linoleum by using two Latin words: linum, which means flax, and oleum, which means oil.

By about 1900, Walton invented a straight line inlay machine which produced linoleum in various patterns. Manufacturers still make linoleum by Walton's basic method, but the modern process is much faster.

By the time the 1950s came along, the use of linoleum started to decline as floor coverings made of various vinyl plastics replaced it in many homes and offices. The new synthetic materials can resist moisture and chemicals better than linoleum can.

To make linoleum, a manufacturer first mixes linseed oil and oxygen in a tank. This process of oxidation changes the oil into a rubbery substance.

Heat and certain gums are added to strengthen the mixture. The resulting linoleum cement is then stored for several days to give it even greater toughness. After the cement has reached the desired strength, it is put into a mixer. There, pigments and such filler materials as ground cork and wood flour are added.

A machine calenders or presses the substance until it is glossy. The machine then applies it to a backing sheet of burlap or felt. The backed linoleum is then dried and hardened in an oven.

After the heating, which is called stowing, the product gets a coating of laquer or wax. The finished linoleum is cut and inspected and then shipped in rolls.

There are two kinds of linoleum: plain linoleum and molded inlaid linoleum.

Molded inlaid linoleum in elaborate designs accounts for most of the linoleum used today. A machine puts ingredients of different colors through a series of stencils onto a backing sheet.

After the colors are arranged in the proper design, they are pressed onto the backing sheet. The material is then ready for stowing.

Plain linoleum is made of a single color by adding a coloring pigment along with the filler. Plain linoleum is called battleship linoleum because it was once used extensively in warships. Battleship linoleum may be colored black, brown, gray or green.

Today plain linoleum is used extensively for linoleum block printing.

Vinyl floor coverings that are being used in place of linoleum these days can be produced faster and in a greater variety of colors and patterns.

Even newer kinds of floor coverings perform better than vinyl types. These new kinds have special surfaces that shine without being waxed.