Looking at the threaded(?) stopper with a handle onto it. I believe it could be a pewter canteen/food holder perhaps to service the need of travelers or field workers.
Pewter is a malleable metal alloy, traditionally 85 -95% Tin, with the remainder consisting of Copper, Antimony, Bismuth and sometimes, less commonly today, Lead. Silver is also sometimes used. Copper and Antimony act as hardeners while Lead is common in the lower grades of Pewter, which have a bluish tint. It has a melting point, around 338 – 446 F ( 170 – 230 C ), depending on the exact mixture.
Pewter was first used around the beginning of the Bronze Age in the Near East. The earliest piece of Pewter found is from an Egyptian tomb from 1450 BC. Pewters containing Lead are no longer used in items such as cups, plates, or jewelry ) that will come in contact with the human body due to health concerns stemming from the Lead content. Modern Pewters are available that are completely free of Lead, although many Pewters containing Lead are still being produced for other purposes.
Pewter is used in decorative objects, mainly collectible statuettes and figurines, game figures, aircraft and other models, (replica ) coins, pendants, and plated jewelry.