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. Refraction and muscular imbalance, as simplified through the use of the ski-optometer. Fig. 12—(A. and B.)—This unique, patented split-spring device of screwless construction, securely holds all movable parts. In case of repair, they may be removed with the blade of a knife. racy and a lifetime of endurance. Particularand detailed attention has been given to thenovel means of eliminating screw^s vs^hicheither bind, create friction or continuallyw^ork loose, causing false indications of find-ings on scales of measurements; hence correctand accurate indications are insured in the [35] Refracti
. Refraction and muscular imbalance, as simplified through the use of the ski-optometer. Fig. 12—(A. and B.)—This unique, patented split-spring device of screwless construction, securely holds all movable parts. In case of repair, they may be removed with the blade of a knife. racy and a lifetime of endurance. Particularand detailed attention has been given to thenovel means of eliminating screw^s vs^hicheither bind, create friction or continuallyw^ork loose, causing false indications of find-ings on scales of measurements; hence correctand accurate indications are insured in the [35] Refraction and Muscular Imbalance Ski-optometer by means of a split spring-washer construction similar to that of an auto>mobile tires detachable rim (Fig. 12). This patented spring-washer constructionsecurely holds the phorometer lenses, the ro-tary prism and the revolving cylinder lenscells. Whenever necessary, or in case of repair,these parts may be readily removed with theblade of a knife. [36] Chapter V CONDENSED PROCEDURE FOR MAKING SPHERE AND CYLINDER TEST WITH THE SKI-OPTOMETE
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Keywords: ., bookcentury1900, bookdecade1920, bookidrefractionmu, bookyear1921