STUDENTS OF SPORTS trivia quizzes will have an easy time fielding this one: What weighs less than six ounces, is wound and bound in Haiti, has a cork middle surrounded by black rubber wrapped in red rubber that is encased by 219 yards of gray and white wool, 150 yards of cotton and has a hide cover sealed with red stiching? By anyone's ballpark estimate, that's a baseball. Now for the hard question: Why is it being punded over so many more fences this year? According to Sports Illustrated, the current home-run output in the major leagues is up 35 per cent from last year. Though June 2, the slugging percentage is 402. Last year, it was .368.

Intrigued by the figured and, no doubt, by the cries of pitchers that a rabbit ball was on the loose, Sports Illustrated commissioned a testing laboratory to determine if indeed the fence-busting was caused by liverlier balls. Or was it merely greater salaries in baseball history? The results suggest new life in the baseballs, not the batters. In tests for resilience and compression, the scientist discovered that the 1977 balls is liverlier than the 1976 ball. It is a harder object as well, as fact confirmed by butcher near the lab who put a 1977 ball through his meat cutter and found it more difficult to spilt.

On our last occasion to discuss the quality of spheres used by athletes, we addressed the sliceless and hookless golf ball. Mildly teed off, we though the idea deserved to be hit out of bounds, as difficult as that might have been, given the ball's properties. We saw no reason to make golf less challenging. In the case of baseballs, however, we're not so sure. A home run is still the most soul-stirring spectacle in the game for many spectators, and a few more of them every year, with some help from the factory, can do no harm-to the hitters. Moreover, rabbity as the 1977 ball may be, the specifications allow it to be even more lively. But what of the pitchers? For their sake, lets wait to see how new ball, but the pitchers have still to make their case.