The Mechanics of Fitting Glasses —— Giving Complete Information Concerning Fitting, Adjusting and Prescribing Eyeglass and Spectacle Frames and Mountings, and Covering All Mechanical Work Within the Province of the Refractionist

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ISBN: 9781332155644 出版年：2016 页码：84 Robert D Pettet Forgotten Books

How to ascertain the position of the plus and minus cylinder in compound lenses by simple inspection. How to construct a chart to measure prisms and to detect a prism power in lenses.