This is an authentic 8 oz British Admiralty War Department cobalt blue poison bottle featuring the classic broad arrow (“↑”) mark, which signified ownership by the British government. These bottles were issued during the late 19th to early 20th centuries and were used by the War Department to store toxic or hazardous substances—most often chemicals, disinfectants, or medical poisons—meant for military or naval use.

The deep cobalt color served a practical purpose: it warned handlers that the contents were dangerous, as color-coded glass was commonly used before standardized labeling became widespread. The raised lettering and arrow emblem were both functional and symbolic, ensuring the bottle’s identity remained even if paper labels deteriorated.

This particular example stands 6½ inches tall, holds approximately 8 ounces, and retains its original glass stopper, which is firmly attached and does not come off. There is still some original liquid remaining inside the bottle. The glass shows the expected signs of age, including bubbles and mold marks typical of early machine or hand-blown manufacturing.

These bottles are highly collectible today, valued for their rich color, historical connection to British maritime and military operations, and distinctive design that captures a bygone era of medical and chemical safety practices.