. A Reference handbook of the medical sciences : embracing the entire range of scientific and practical medicine and allied science. Fig. 4595.—Brudenell Carters Modi-fication of Forsters Perimeter. 660 REFERENCE HANDBOOK OF THE MEDICAL SCIENCES. blackened on its inner surface, and graduated on its pos-terior surface in degrees ; the zero of the division beingat its summit or apex. The arc is joined at its apex to avertical standard, around which it may be rotated in acomplete circle. The position of the arc is marked bya pointer, and the two move together around a dialwhich is
. A Reference handbook of the medical sciences : embracing the entire range of scientific and practical medicine and allied science. Fig. 4595.—Brudenell Carters Modi-fication of Forsters Perimeter. 660 REFERENCE HANDBOOK OF THE MEDICAL SCIENCES. blackened on its inner surface, and graduated on its pos-terior surface in degrees ; the zero of the division beingat its summit or apex. The arc is joined at its apex to avertical standard, around which it may be rotated in acomplete circle. The position of the arc is marked bya pointer, and the two move together around a dialwhich is fastened tothe posterior surfaceof the head of thestandard. Two mov-able black frames areattached to the arc,destined to hold ec-centric objects, suchas figures, or bits ofwhite or colored pa-per. The distance ofthe test-object fromthe summit or apex. Fig. -1596.—Houdins Diopsimeter. of the arc is indicated on thesubdivisions of the eye of the patient shouldbe placed at the centre ofthe hemisphere described bythe arc. For this purposea second standard, smallerand shorter than the first, isplaced in front of the is destined as a support for the head, and has at itsupper extremity a support for the chin, which is suffi-ciently broad to admit of the chin being placed on theright or left of a small shaft or stem which rises from thetop of the standard. The upper end of this stem is curvedforward and rests against the inferior orbital margin ofthe eye under examination. The stem itself is immova-ble, but the chin-support may be raised or lowered asmay be desired, and may also be rotated roundits vertical axis to avoid causes of error due toprominence of the nose or of the superior orbitalmargin. The observer stands in front of the pa-tient and moves eccentric objects along the arcfrom its extremities toward the ap
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectmedicine, bookyear188
