Jesse Ramsden

Jesse Ramsden was a British mathematician and maker of astronomical and scientific instruments. His reputation was built on the engraving and design of dividing engines, which allowed high accuracy measurements of angles and lengths in instruments. He produced astronomical instruments especially well known for maritime use, where they were needed for measuring latitudes, and surveying instruments widely used for cartography and land survey across the British Empire and beyond. An achromatic eyepiece he invented for telescopes and microscopes continues to be known as the Ramsden eyepiece.