Winemaker Larry Sharrott 3d looked through a kaleidoscopelike instrument called a refractometer, measuring the sugar content of a just-pressed batch of chardonnay grapes. He liked what he saw. This summer's hot, dry weather has produced the best grape harvest in South Jersey in years, growers say - high in sugars and full in flavor. "Napalike," Sharrott said. Sweet wines made with American grape varieties or other fruits - cranberries, peaches, blueberries - have long dominated New Jersey's wine industry. But with the number of wineries soaring in the last decade from 12 to at least 40, that's changing.