An antique Georgian Stanhope lens c.1815, a simple form of microscope lens, invented by Charles, 3rd Earl Stanhope. This type of lens is a plano-convex glass cylinder, with one convex and one flat end, which could be used for rudimentary microscopy, magnification of small objects, or other scientific investigation. This example has a handle of 'German silver' (nickel plated brass), attached to a loop around the lens. The lens is ground so that when its flat face is placed on a surface, it is in focus. An almost identical Stanhope lens can be seen in the collection of the University of Arizona College of Optical Science.
Relatively simple and economical to make, the Stanhope was popular in the early 19th century when microscopy was in its infancy. It was apparently used by physicians for examining transparent materials such as crystals and fluids. The French photographer René Dagron (1817-1900) produced a modified version of the Stanhope lens in the 1860s, miniaturising the lens so it could be used with his microscopic images in photographic jewels which were also (and somewhat confusingly) known as Stanhopes.
Charles Stanhope, 3rd Earl Stanhope (1753-1816):Stanhope was British politician and an accomplished scientist. At University in Geneva he studied mathematics under Georges-Louis Le Sage. Electricity was another of the subjects which he studied, and he produced a work entitled Principles of Electricity in 1779. He was elected a fellow of the Royal Society in November 1772, and devoted a large part of his income to experiments in science and philosophy. He invented a method of securing buildings from fire (which, however, proved impracticable), the first iron printing press, and the lens which bear his name. His other work included a monochord for tuning musical instruments, improvements in canal locks, experiments in steam navigation, and two calculating machines. He was elected a member of the American Philosophical Society in 1774. Stanhope was also elected a member of the American Antiquarian Society in 1816.
Condition: The lens is in very good condition, with a couple of minor scratches, two tiny chips on the bottom edge, and some wear to the centre section of the bottom face of the lens. The view through the lens is very good.
Dimensions: Lens: 30mm diameter, 35mm height, Length inc. handle: 70mm