This is an early 20th century cut crystal ship's decanter. A ship decanter is denoted by the wide flat bottom shape and taller conical neck. The shape would help keep the decanter from tipping over when the ship is rolling. In especially rough seas, the decanter is placed on a slightly dampened cloth for better 'grip'. Along with the cut decoration, there is an added wheel cut engraved decoration with a nautical theme of a directional compass, or cardinal point, anchors and stylized waves. The underside is signed "Engd (for engraved) by D.D. Fair. It is more likely that D.D. Fair only added the nautical theme decoration and was not responsible for cutting the crystal. There is not a listed glass artisan by that name. The estimate is based on actual recent past recorded auction sales of comparables. Retail 'asking prices' can be higher and vary.