Boston — Maybe Americans just couldn't get used to the idea of batting a ball a country kilometer, donning a 10-liter hat, or eating a half-kilo cake.
Whether the real reasons are more scientific - or just as impulsive - the failure of the metric system to take hold in this country seems aptly symbolized by the scheduled demise of the US Metric Board on Sept. 30.
Touted as the wave of the future, metric conversion became policy in the United States with the passage of the Metric Conversion Act of 1975. It was to be meters for yards, grams for ounces, and liters for gallons. The British uniform standard of measure (yards, ounces, gallons, etc.) might have been quaint, but it was also archaic.
It's now seven years later, and nobody is packing away his ruler yet.
''The public has pretty much abandoned the idea,'' says Seaver Leslie, head of Americans for Customary Weight and Measure, a group that opposes the change. ''They realize the conversion effort was in their hands - it wasn't a government mandate - and they rejected it.''
In spite of the naysaying, liter and meter partisans aren't conceding an inch. To them the switch to metric isn't a matter of preference, it's simply sound finance.
''In terms of our position in international trade, we're going to find ourselves increasingly isolated in trying to do business overseas if we don't continue going metric,'' says David Gorin, director of the privately sponsored American National Metric Council.
Theodore Farfaglia, executive director of the US Metric Board, agrees. ''The driving force is an economic one, not a matter of the best system of weight and measure.''
The metric system is used in all but a handful of countries around the globe. And with the rise of overseas competitors whose products rival US exports for quality, US firms are finding it increasingly difficult to penetrate foreign markets with goods based on the uniform standard of measure.
Some US corporations took the hint long ago. General Motors will be completely metric by 1983, as will IBM.
Most metric supporters recommend a go-slow conversion policy tied to reindustrialization, or simply coupled to a corporation's upgrading of machinery.
Despite the strides made in industry, metrics still haven't caught on with the public. In fact, many of the vestiges of the initial drive are disappearing. The Federal Highway Administration was compelled to remove some metric highway signs because of public disapproval, and vandalism. A number of service stations that attempted to sell gasoline by the liter have switched back, and some states have even passed laws to prevent a metric changeover.
Educating the consumer about metrics was the US Metric Board's primary purpose. When the Reagan administration decided to eliminate the board in a budget-cutting move, it declared the board's purpose accomplished. With $300,000 a year instead of the Metric Board's $2 million, the Commerce Department will carry on some of the board's functions - primarily cajoling business to continue the conversion process.
However, not everyone appears to believe that private industry will spearhead the drive to metrification. That role may well be performed by the nation's school systems. Already a number of states have mandatory metric education, and all 50 have at least some instruction in it.
Frank Perkins, associate provost at the Massachusetts Institute of Technology , reports that most of the students entering the university are literate in metrics. He sees complete acceptance of metric conversion by the early 21st century, mostly because of grade-school instruction in it.