Brass Dumpy Level 5"

By the mid-1700s, after a century of design, research, and testing, new lenses and mirrors allowed the ship telescope to become a more common and available tool. During this time the Industrial Revolution lead to advances in construction and production, making it possible for the first time to reproduce the antique brass telescope on a larger scale. With the development of the achromatic lens in 1758, a double lens reducing distortion and increasing magnification, it became possible to manufacture the antique brass telescope with a manageable, hand-held size. With these new models, the Age of Sail saw a dramatic development in the field of hydrography, or charting bodies of water, and cartography, or map making. Using the dumpy level, crafting these maps of land and sea became a much more scientific process, allowing for the creation of the most accurate maps the world had ever seen. With two basic components, the tribrach and the small brass telescope, the dumpy measured horizontal lines of sight, with the telescope rotating around a vertical axis. The Tribrach was a set of four foot screws, allowing for the telescope to be balanced properly for an accurate reading. Using the dumpy antique brass telescope, sailors expanded knowledge of the new world as they sailed across the vast seas, changing history and pushing sailing into a new era.