Scale Vernier Unit Test Plate Ott's K.&E., No. 4230 Coradi's Compensating No. Ratio Linear Area Actual Relative Area Reading Setting Constant Setting Constant Setting Constant Setting Constant 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Ft. Ft. Ft. Sq. Ft. Sq. Ft. Sq. Ft. Sq. Ft. Units ½ mm Units ½ mm Units ½ mm Units ½ mm Units 1 1:10 1 = 10 1=100 .0144 .01 10.764 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 2 1:20 1 = 20 1=400 .0144 .04 43.056 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 3 1:30 1 = 30 1=900 .0144 .09 96.876 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 4 1:40 1 = 40 1=1600 .0144 .16 172.224 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 5 1:50 1 = 50 1=2500 .0144 .25 269.10 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 6 1:60 1 = 60 1=3600 .0144 .36 387.50 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 7 1:70 1 = 70 1=4900 .0144 .49 527.43 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 8 1:80 1 = 80 1=6400 .0144 .64 688.89 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 9 1:90 1 = 90 1=8100 .0144 .81 871.88 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _ 10 1:100 1 = 100 1=10000 .0144 1.00 1076.41 1076.4 303.5 17458 52.6 18010 305.9 22881 _ _ _ _ _ _ _ _