Spencer's Foco-meter
 Catalogue Number: 4166 Spencer's Foco-meter Category: Equipment Sub-Category: Vertometer, lensometer, focimeter Corporation: Spencer Optical Mfg Co Year Of Publication/Manufacture: c 1890 Time Period: 19th C Place Of Publication/Manufacture: New York, USA Publisher/Manufacturer: Spencer Optical Mfg Co Description Of Item: Hand-held non-illuminated vertometer (or focimeter or lensometer), consisting of two sliding metal tubes and glass lenses. It has an eyepiece at one end and a cross-hair target at the other. The device is used by inserting the lens to be measured into a slot and holding the meter up to a light source. The observer then looks through the instrument and adjusts the postion of the inner barrel to attain a clear image of the target. The lens power is then read from a calibrated scale on the inner barrel. Length extends from 310mm to 450mm, diameter 39mm. The design of this instrument is based on the phakometers of Snellen and Badal. Historical Significance: Charles Spencer was the first American to successfully make microscopes in the U.S.A. and ran the only USA firm to do so until 1849. It published its first catalogue in 1838. In 1865 he began operating as C. A. Spencer and Sons. In 1873 Spencer and his sons moved from the original shop in Canastota, New York to Geneva, New York. After Charles' death in 1881 the business was carried on by his son Herbert, who, after a time moved to Cleveland, Ohio, and then, in 1890, to Buffalo, New York, where the company remained. For a short time, between 1890 and 1895 the company became known as Spencer and Smith. The Spencer Company was incorporated in 1895, using the name Spencer Lens Company up into the 1940's. American Optical was established in 1833 as a small spectacle manufacturing concern in Southbridge, Massachusetts. The company grew rapidly, gradually acquiring additional facilities for manufacturing a range of optical products. In 1935 this expansion lead to its purchasing the Spencer Lens Company of Buffalo, New York. How Acquired: Donated by Pamela Sutton Date Acquired: March 2022 Condition: Very good Location: Archive room. West wall. Unit 3 Drawer 2 |