“Day or Night” Telescope
This telescope is representative of the type commonly used aboard ships in the early 1800s, and was reportedly owned by USS Constitution Captain Isaac Hull, though this is unconfirmed. The large objective lens is designed to increase the amount of light allowed in, consequently making dim images at night appear visible from a distance. Telescopes of this kind, marketed as “Day or Night,” were particularly valuable to watch officers stationed on deck at night. It was manufactured by the renowned firm of Thomas Harris & Son, which was established in London in 1780 and became one of the best known designers and manufacturers of optical instruments in the first half of the 19th century. Despite the American Revolution and the War of 1812, British-made navigational instruments such as this one remained common on United States warships and commercial vessels throughout the period, as Americans had yet to develop a comparable level of precision manufacturing.