This rare treasure is known as an Optometer — one of the earliest self-refraction devices used to test eyesight in the 19th century. Constructed of wood with a glass focus lens, these ingenious instruments were commonly found in general stores during the 1800s, allowing customers to self-test their vision before selecting or ordering spectacles without the need for a professional examination.
According to the Bennion reference, later models from 1870 featured boxwood extensions and brass view lenses, helping us date this particular example to the earlier period of 1850 to 1870. After 1870, manufacturers transitioned to brass and boxwood construction, and by 1875 all-brass models became standard — making all-wood examples like this one among the earliest and most desirable for collectors.
This example remains in working order, a remarkable feat for an instrument of this age. The faint but readable graduated markings allowed users to slide one section until focus became clear, indicating the lens power needed for their vision. Measuring 11½ inches long and 1¼ inches tall, it retains its original wooden construction with four small age cracks — honest wear that speaks to nearly two centuries of existence.
