These items are antique American salt-glazed stoneware shoulder jugs dating from the late 19th century to early 20th century (circa 1890–1915).
The M. Salzman Co. Jug: The center item is a highly collectible pre-Prohibition advertising whiskey jug. Founded by Morris Salzman, an Austrian immigrant, the company operated prominent saloons in Brooklyn and Buffalo, New York, between 1905 and 1915. Salzman famously bought out the Empire Distillery and stenciled these pieces with his signature slogan, "Purity Above All".
The Large Numbers: The bold stenciled "2", "3" and "4" denote the liquid capacity in gallons, which helped merchants easily measure stock volume.