This is an Elijah cup, which is set out for the prophet Elijah during the Passover seder. Elijah is said to visit the seder of every Jew.
United States Geological Survey, 1936
United States Geological Survey, 1940
United States Geological Survey, 1938
United States Geological Survey, 1935
United States Geological Survey, 1939
United States Geological Survey, 1937
United States Geological Survey, 1760