Arc perimeter on stand
 Catalogue Number: 3321 Arc perimeter on stand Category: Equipment Sub-Category: Perimeter, visual field analyser Year Of Publication/Manufacture: 1930s Time Period: 1900 to 1939 Description Of Item: Arc perimeter for the measurement of visual field losses on a stand, overall height 480 mm at lowest height adjustment, arc 160 mm radius, black enamel metal base 125 mm diameter, chrome metal stem adjustable in height. Arc rotation marked with a angular degree scale. Arc has a white degree scale to 90 degrees right and left and the outside of the arc. Turn screw on height adjustment marked 'Trennery Melbourne'. Historical Significance: Measurement of loss of peripheral visual fields dates from 1856 (von Graefe) and the first arc perimeter was devised in 1857 by Hermann Aubert. The hand held arc perimeter was devised in 1888 for use at a patient's bedside. This item is a small arc perimeter on a stand but it possible it began life as a hand held perimeter and the stand was added later, or that it was made to be either on a stand or with a handle. This item was donated to the Museum in the 1970s but the old card catalogue record has been lost. The turn screw for fixing the stand height is marked 'Trennery Melbourne' but it may be a replacement screw. Condition: Fair. Arc stem damaged (Handle with care) Location: Archive room. East wall slat board |