Though "trick" vessels date back to the 14th century, it wasn't until the late 17th century that puzzle-jugs became more widely fashionable and production increased in Europe and in China. Essentially portable drinking games, they challenged the uninitiated to figure out how to consume the alcohol inside without spilling the vessel's contents and amused observers. Often a straw concealed within the handle led to at least one open spout at the rim. The (hopeful) imbiber needed to either use the correct spout, or cover several open apertures to create the suction needed to consume the alcohol within. The two sets of initials on the present jug likely indicate it was made in celebration of a marriage.