A big argument in support of the trade bill was that it would give the United States a "level playing field" on which to scramble for its fair share of international commerce. It turns out that the legislation also tries to dictate how the field shall be measured.

An obscure section of the bill, which was signed by President Reagan, designates the metric system as the preferred method of measurement for trade and commerce.It says that by 1993, federal agencies should "use the metric system of measurement in procurement, grants, and other business-related activities, except to the extent that such use is impractical or is likely to cause significant inefficiency or loss of markets to U.S. firms." That last clause gives opponents an out, but the total impact of the new law should be to boost conversion to the metric system.

Such conversion would be beneficial to U.S. trade. Since 98 percent of the world uses the metric system, it seems logical to assume that American merchants would be on more solid ground in talking to prospective foreign customers about American goods measured in liters, meters, grams, and metric tons, than in quarts, yards, ounces, and short tons.

Still, there is no guarantee of popular support for a conversion. The metric system, devised by a French church vicar in 1670, has been legal in the United States since Congress passed and the president signed a law to that effect in 1866. Despite periodic attempts since then to advance the system, the American public has shown an impressive lack of interest.

Let's hope that the trade bill stirs new interest in educating Americans on the system that uses multiples of 10 to measure things. Once people get the hang of it, they probably will wonder why the country didn't convert a long time ago.