If you were dining at the Morris-Jumel Mansion in the 1760s with Roger and Mary Morris, you might have used a wineglass that looked like this (in less fragmentary form!). The white corkscrew ornamentation on the stem is referred to as an "opaque twist." Such decoration was popular in Georgian England; glasses bearing it would have been imported from the United Kingdom to the American colonies.
The fragment was found during an archaeological dig at Morrisania, the estate of Roger Morris's contemporary (but not relation) Lewis Morris. Most of Lewis's estate was located in what is now the Bronx—where the glass remnant is located today. It is on exhibit at the Valentine-Varian House (1758), home of the Bronx Historical Society. This set of opaque-twist wineglasses, made about 1760, gives you an idea of what the vessel might have looked like in its prime.